Rabels Zeitschrift

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Max-Planck-Institute for foreign and international Private Law

Rabels Zeitschrift

for foreign and international Private Law

Hein Kötz
in honor of his 60th Birthday
Part I

Volume 59 (1995)Issue 3-4 (October)

General Principles of UN-Sales Law

By Ulrich Magnus, Hamburg[*]

Lisa Haberfellner, trans.

Table of Contents

1. Kötz's criticism of International Uniform Law
2. Current solutions
3. History of Art. 7(2) CISG
4. Initial methodological questions

a) Filling the gaps

b) Nature and determination of general principles
5. The general principles of the CISG

a) State of discussion

b) Selected principles

(1) Party autonomy

(2) Pacta sunt servanda

(3) Good faith

(4) Reliance protection

(5) Standard of reasonableness

(6) Forfeiture

(7) Prevalence of usage

(8) Lack of form requirements

(9) Favor contractus

(10) Duty to avoid damages

(11) General duty to cooperate

(12) Duty to pay damages

(13) Concurrent performance

(14) Set-off of claims arising under the Convention

(15) Retention right

(16) Passing of risk only in case of identification of the goods to the contract

(17) Passing of encumbrances and fruits with passing of risk

(18) Calculation of time limits

(19) Theory of dispatch

(20) Theory of receipt

(21) Maturity without request

(22) Imputation of third party conduct and knowledge

(23) Currency

(24) Place of performance for payment claims

(25) Interest

(26) Burden of proof

c) Rules not to be interpreted as general principles

(1) Interest rate

(2) Seniority of payment claims

d) Analysis
6. The UNIDROIT-Principles

a) Origin and objective

b) Application of the "Principles" as general principles within the framework of the CISG?
7. Conclusion

1. Kötz's criticism of International Uniform Law

Hardly anybody has described an Achilles' heel of Conventions creating uniform law more pointedly than Kötz:

"The person looking at the currently effective Uniform Law from a certain distance will be surprised by its selective and fragmentary nature ..."[1]

"Indeed it's a scary thought that the countless current undertakings of unifying and adjusting laws develop into completed texts and that the stream of these texts could then be directed to the already overburdened mills of national legislators."[2]

"However, at a closer look the question appears justified whether uniform law, in as far as it intends to simplify law, does not find itself in the position of Heracles who cut off Hydra's snake head only to be confronted with three new ones instead."[3]

Of course, these shortfalls of International Uniform Law partially are in the nature of things. Efforts toward unifying law cannot start right away with the -- even worldwide -- codification of, for example, the entire Private Law or even only the entire Law of Contracts. Such projects would squander tremendous energies and yet remain a utopia. For if law -- and this truism is all the more true for International Uniform Law than on a national level -- shall find acceptance, it has to be based on legal doctrines shared by the majority of those who will be subject to this law. In light of the social, economical, political, and philosophical differences which separate today's nations and definitely affect the sensitive areas of Private Law (e.g., consumer protection etc.), already existing common basic doctrines can be identified only to a very limited extent. Therefore, an attempt to unify the law of several independent nations in my opinion as a matter of necessity -- has to be made selectively for specific areas first; and experience shows that it has always been done this way.

To illustrate, the ambitious Code des Obligations of 1929[4], which was intended to unify the entire Law of Contracts for France and Italy in numerous articles never went into effect. Even in the close legislative collaboration of the Nordic states there never was a global codification of larger areas, but only single uniform codes such as the largely identical Nordic Sales Laws.[5] The U.S. Uniform Commercial Code (UCC) -- a quite comprehensive legislative work -- is hardly imaginable without its selective predecessors such as the Uniform Sales Act of 1906.

The selective approach of unifying efforts inevitably entails a certain fragmentary character of the regulation. Even in Conventions as far-reaching as the UN-Sales Law[6], which intends to comprehensively regulate the relationships of parties to a sales contract, questions of the general law of obligations remain open and the incorporation in the respective national legal systems remains quite problematic.[7]

The careful reader of Kötz will realize that by criticizing -- legislative -- attempts to unify law he by no means rejected them completely. Rather, Kötz legitimately warns that such a unification has to be attempted moderately, that especially the coordination of various unification attempts and unifying organizations has to be improved. Every reasonable person will agree with Kötz's opinion that a multitude of independent co-existing Conventions is not a desirable permanent state of affairs.

2. Current solutions

The structural shortfalls of international Conventions, which lie in their fragmentary nature, can be remedied only to a limited extent by formulating the respective provisions as precisely as possible. Doubtful issues and problems of incorporation will always remain, as even the example of the CISG still shows[8], which not only in that regard has been prepared with special care.

Another possible solution which shall be analyzed more closely in this context is the possibility of referring to the "general principles" for cases of doubtful interpretation and filling of gaps. Again, the UN-Sales Law with its Art. 7(2) can serve as an illustration:

"Questions concerning matters governed by this Convention which are not expressly settled in it are to be settled in conformity with the general principles on which it is based or, in the absence of such principles, in conformity with the law applicable by virtue of the rules of private international law."[9]

More recent Conventions concerning Private Law issues have adopted the same formulation.[10] The following lines, which are dedicated to the honoree, examine the soundness of this approach.

3. History of Art. 7(2) CISG

A similar version of the current Art. 7(2) CISG was already included in the first draft of the Uniform Sales Law of 1935.

"Art. 11. If this Statute does not expressly settle a question and does not formally provide for application of a national law, the court decides in conformity with the general principles on which this Statute is based."[11]

Rabel justified this provision as follows:

"Art. 11 establishes the general principle according to which the gaps in this Statute are to be filled. Since the judges applying this Statute are subject to different laws and used to their application, the greatest danger for maintaining a truly uniform legal situation lies in diverging judicial interpretations. We have to fear strongly that the courts will either consciously or subconsciously use their national law to fill gaps. Thus the desired legal uniformity would quickly fall apart. [...] However, a common basis for decision-making is absolutely indispensable. Therefore, this Article provides that cases not expressly settled in this Statute nevertheless are subject to it and thus have to be resolved in the spirit of the Statute in conformity with the principles permeating it. These principles are called principes généraux, a formulation which resembles the famous Art. 38 of the Statute of the International Court of Justice at The Hague and refers -- with like generosity but considerably less difficulties -- to the common features of legal doctrines, which are to be found through comparative legal analysis, as a source of law. [...]"[12]

Thus, recourse to the national law applicable by virtue of the rules of private international law shall be admissible, only in those cases, however, in which the Convention "formally" ("formellement") made a provision to that effect.[13] The utilization of private international law disappeared in the Hague Sales Law. Pursuant to Art. 17 EKG[*] issues not expressly settled in this Statute were to be decided in conformity with the general principles on which this Statute was based. The rules of private international law were explicitly excluded in Art. 2 EKG, "unless otherwise provided in this Statute". This was mostly interpreted to mean that gaps in the Hague Law would have to be filled exclusively in conformity with the general principles.[14] If such principles would not result from the Uniform Sales Law itself, they would have to be developed through comparative legal analysis.[15] Others wanted to utilize private international law in the event that general principles could not be ascertained in the Uniform Law itself.[16]

The court decisions on the EKG have restricted themselves to developing only a few general principles from the Uniform Law itself.[17] If this was not possible, the issue was mostly regarded as not subject to the Convention and decided pursuant to the law applicable according to the rules of private international law.[18]

The adoption of Art. 7(2) into the CISG was quite controversial and had been ruled out completely in the early stages of the discussions.[19] Even in the Diplomatic Conference of 1980, the provision, which had been accused of ambiguity, remained disputed. The current version is based on a compromise suggested by the GDR[20], which combined general principles and private international law and found a slight majority.

The entire Art. 7 CISG in its currently valid formulation has also been adopted by the later international Conventions concerning Private Law issues.[21] Thus, by now the provision is a fixed part of the general regulations of such Conventions.

4. Initial Methodological questions

The following methodological considerations are based on Art. 7 CISG, but can also be applied to the parallel provisions, e.g., in the Agency-, Leasing-, Factoring- or other Conventions concerning Private Law issues.

a) Filling of gaps

Art. 7(2) CISG is primarily designed to fill gaps -- as opposed to matters of interpretation which are the primary subject of Art. 7(1) CISG. If we want to take recourse to the general principles of Art. 7(2) CISG, we first have to decide that the legal issue at hand concerns a matter governed by this Convention yet not expressly settled by it ("internal gap").[22] Thus, the basic decision regarding the applicability of the Convention has -- at least theoretically -- been made if general principles pursuant to Art. 7(2) CISG come into play. Yet, except for the cases clearly exempt from the CISG (such as the transfer of property), the borderline between legal issues subject to the CISG and those not governed by it often is rather uncertain. For example, does the CISG cover claims arising out of the dealings before the actual conclusion of the contract? Are setoffs at least partially regulated? Does the burden of proof belong into the CISG? Very often there will be a correlation between the existence of general principles on the one hand and the application of the Convention on the other hand, in that the Convention is applicable if and because general principles can be ascertained. If, however, general principles are lacking, the respective national law is applicable, regardless of whether the legal issue is basically covered by or exempt from the CISG.

This procedure is not objectionable from a methodological perspective as long as it is not overstretched. As far as legal thoughts subject to generalization can be derived from the Convention itself with sufficient substantiation, this procedure promotes an application of the Convention that is as uniform as possible. It is precisely this uniform application that Art. 7 CISG and the respective provisions in the more recent Conventions unifying Private Law issues intend to achieve.

Yet, it is problematic to take recourse to general principles outside of the Convention.

For example, considering the wording and history of Art. 7 CISG, the utilization of the "general legal principles recognized by the civilized nations" referred to in Art 38 of the Statute of the International Court of Justice is out of the question. Although this thought, as explicated above[23], has been the basis for this provision to a certain extent in the draft of 1935, it had not been adopted in its entirety even at that time.[24] The wording of Art. 7(2) CISG allows only the consideration of those principles on which the Convention "is based" (as formulated in the weighty English text[25], whereas the French version uses the somewhat weaker "dont elle s'inspire"). Thus, the fact that a particular general principle shall apply to the Convention has to be expressed in the Convention itself or has to result from it with sufficient clarity. Without such a link to text and structure of the Convention the utilization of general principles becomes arbitrary and the goal of uniform interpretation is more endangered than furthered.

This also generally excludes the possibility to develop -- based on a comparative legal analysis -- common principles either from the law of all nations or even only from the law of the Contracting States of the CISG for the purpose of filling gaps ad hoc for a specific case.[26] In this case, too, the link between principles developed in such manner and the CISG as well as the truly general acceptance of such principles is lacking. In addition, the task of conducting an intensive comparative legal analysis in order to ascertain a general principle for a specific case at hand would be too much for a single person applying the Convention. Rather, the prevailing trend in many of cases will probably be to regard the solution of one's own law as generally valid. Such a procedure cannot promote a uniform interpretation and application of the CISG.

Yet, even if recourse to general principles outside the CISG is generally out of the question, an exception has to be made if and to the extent that general basic principles develop or are developed which are internationally coordinated and actually find general acceptance. Even if the CISG were not based on these principles initially, such a development should not be impeded.[27] Rather, in this way an -- often criticized -- "petification" of once created Uniform Law[28] could be counteracted. However, it has to be emphasized again that such a procedure requires the international acceptance of "general principles" created in such manner. In how far the "Principles of International Commercial Contracts"[29] developed by UNIDROIT fulfill this requirement shall be examined more closely under 6. below.

In general, however, Art. 7(2) CISG legitimately restricts itself to those general principles which form the basis of the CISG, inspired it and for which indications can be found in the Convention itself.

b) Nature and determination of general principles

General principles can regularly be derived from the CISG -- and other Uniform Law Conventions -- in four ways:[30] First, some provisions explicitly claim their applicability to the entire Convention, for example in the CISG Art. 6 (principle of party autonomy), Art. 7(1) (principle of good faith) or Art. 11 (principle of lack of form requirements). Their character as a general provision results both from their wording and their position in the Convention's system. In the CISG, they are incorporated in the part "General Provisions". Strictly speaking, they might not be included in the general principles contemplated by Art. 7(2) CISG, since they expressly indicate their general applicability and thus do not constitute principles "hidden in the law [...] without having been directly expressed".[31] However, due to their fundamental importance, which occasionally goes beyond their wording, it appears justified to regard them as part of the Convention's general principles.[32]

Further, a separate comprehensive thought can be derived from several provisions. For example, Art. 67(2) and 69(2) CISG provide that passing of risk requires identification of the goods to the respective contract. This rule can be extended to those cases in which the question -- as in Art. 68 -- is not expressly regulated.

In addition, single provisions might include legal thoughts which are subject to generalization and are to be applied in similar situations. Art. 20(2) CISG can serve as an example. According to this provision, holidays generally do not extend the period for making a declaration, except if the respective notice could not be delivered due to the holiday. This thought can be generalized to the effect that holidays are included in all time limits (e.g., also for delivery), except if the respective action (e.g., delivery) could not have been taken due to the holiday. In this case the time limit is extended accordingly.[33]

Finally, the overall context can show that a certain basic rule is implicitly assumed. An example in the CISG is the rule "pacta sunt servanda". The sentence is not expressed anywhere, but apparently constitutes the basis for the exemption provision of Art. 79 which determines the cases in which an obligor is discharged from his obligation.

5. The general principles of the CISG

a) State of discussion

To date, jurisdiction on the CISG which has resolved legal issues based on the general principles is restricted to a few judgments.[34] Some commentators hold that only a few general principles can be derived from the CISG.[35] However, the majority of the commentators develops a rather comprehensive -- although differing -- table of possible "general principles".[36] This table corresponds to a great extent to those principles which are specified as the contents of an international lex mercatoria.[37]

b) Selected principles

(1) Party autonomy. -- All agree that the parties' agreements prevail over the provisions of the CISG (Art. 6).[38] Except for the provision of Art. 12 CISG (reservation as to form), the validity issues to be determined in conformity with national law (Art. 4 (a) CISG) and the principle of good faith (Art. 7(1) CISG), the parties' authority to regulate their relationship is unlimited. The CISG only supplements the parties' agreement in so far as the parties did not regulate an issue.

(2) Pacta sunt servanda. -- The basic rule that contracts are binding is not expressly mentioned in the CISG.[39] However, it is implied in numerous provisions, such as Art. 30 and 53 CISG, which determine the duty to deliver and the duty to effect payment. Particularly Arts. 71-73 and 79 show that the binding effect of the contract cannot be avoided in cases such as a simple change of circumstances or frustration of contract, but only if the requirements listed in these provisions are present; without the binding nature of the contract these provisions would not make sense.

(3) Good faith. -- Art. 7(1) CISG stipulates as a general interpretation rule for the CISG "the need to promote ... the observance of good faith in international trade". Pursuant to the wording, this maxim applies only to interpretation of the CISG provisions. However, the vast majority of commentators regards the principle of good faith also as a standard for the interpretation of the parties' agreement and for the entire legal relationship between the parties.[40] However, the principle requires some specification in order to supply an operable decision-making tool for a judge in an actual case. In that respect there is a broad agreement that Art. 7(1) at least contains a prohibition against abuse as well as a prohibition against venire contra factum proprium (actions contrary to prior conduct).[41]

Both features are also to be found in other CISG-provisions: For example, Art. 29(2), second sentence prohibits the abuse of a formal legal position.[42] Art. 80 shows more generally that a party must not take advantage of its own unlawful actions. Article 16(2)(b) (irrevocability of an offer once the offeror has created a situation of reliance)[43] and Art. 50(2) (no price reduction if the creditor unjustifiably rejects cure) can serve as examples of a prohibited venire contra factum proprium.

Sometimes Art. 7(1) CISG is further interpreted to the effect that the parties have to act in conformity with the standards of prudent businessmen in international trade.[44] However, such a rule per se appears too unspecific.[45] To the extent that there is international usage in an industry, it has to be taken into account by virtue of Art. 9 CISG (see also below 5 b [7]). Otherwise, however, such a general principle again would create the danger that the respective judge would incorporate his own national standards into his decision.

(4) Reliance protection. -- There is a close connection between the good faith principle and the principle that a party who has created a situation of reliance, upon which the other party has acted, has to bear the consequences of such situation. The already mentioned Art. 16(2)(b), 29(2), second sentence, but also Art. 35(2)(b) (reliance on seller's special skill) and Art. 42(2)(b) (no liability for title defects if the seller has manufactured the goods in conformity with the buyer's specifications) show that the Convention is based on a general legal thought which can be applied to similar situations. Thus, a seller can no longer assert defects in the buyer's notice of lack of conformity of the goods if the seller himself has caused the impression -- upon which the buyer has relied -- that the seller will investigate the complaints -- which, e.g., were not asserted with sufficient specification -- and then cure the defects.[46] Also, if a party has created the impression that she was willing to modify the contractual terms, she is bound if the other party has already acted in justifiable reliance on this representation.

Of course, the line to those cases subject to the prohibition against venire contra factum proprium is blurred. Yet, a party can only demand reliance protection if she has actually relied upon specific actions by the other party. The prohibition against venire contra factum proprium does not require such a reliance situation.

(5) Standard of reasonableness. -- In numerous provisions the CISG uses the term "reasonable/raisonnable", which is translated into German partially as "vernünftig", partially as "angemessen".[47] Sometimes the term refers to time limits which have to be reasonable (in particular, in Art. 39(1)). Sometimes the provision is concerned with a party's conduct which has to be reasonable. In both cases the general rule of Art. 8 CISG has to be applied. This rule stipulates that, in general, an objective standard has to be applied which is based on the view of a neutral, prudent person in the same situation. However, noticeable relevant circumstances of the case (Art. 8(3) CISG) and international usage (Art. 9 CISG) prevail in that respect.[48]

(6) Forfeiture. -- Further, the concept of forfeiture is closely connected with the good faith principle. According to a controversial, but preferable opinion the CISG, too, contains the thought -- known from many legal systems -- that a party can lose her rights by not asserting them for a longer period of time and thus creating the impression for the debtor that she will not assert these rights at all.[49] This principle can be derived from those provisions establishing the principle of reliance protection in general in the Convention.[50] Thus, recourse to the national law of forfeiture applicable by virtue of the rules of private international law is impossible.[51]

In particular, a case for application of the principle can result in the context of Art. 46(1) CISG which does not designate a time limit for the buyer's right to performance, so that only the national prescription periods, which sometimes are quite long, are applicable. In my opinion, the buyer can forfeit his right to delivery under the CISG if he lets the contract rest for a longer period of time (such as more than one year).

(7) Prevalence of usage. -- Among the general principles of the Convention whose validity is undisputed is the relevance of international trade usage (Art. 9).[52] Widely known usages of international trade in the respective industry should -- beyond the wording of Art. 9 CISG -- generally be utilized to resolve doubts about the interpretation of the Convention itself. However, this possibility can only be taken into consideration if the strict requirements under which Art. 9 recognizes international usage are actually fulfilled: that the usage is internationally known and regularly observed.

(8) Lack of form requirements. -- Article 11 CISG provides for a lack of form requirements -- to the extent that the Contracting State did not make a reservation as to form pursuant to Art 96 in conjunction with Art. 12 -- however, only with respect to contract conclusion and its evidence. Yet, it is legitimate to derive the general principle from this provision that declarations of all kind -- such as notice of lack of conformity, declaration of contract avoidance, etc. -- are not subject to any form requirement under the CISG.[53]

(9) Favor contractus.[54] -- Several provisions show that the CISG will allow contract avoidance only under narrow conditions and as a last resort (see Arts. 25, 34, 37, 47, 48, 49, 63, 64).[55] If possible, an economically not feasible winding up of the sale should be avoided. Only if the gravity of the breach of contract is unacceptable, the aggrieved party has to be able to get out of the contract.[56] This principle also applies in situations of a breach of obligations which are either not expressly regulated by the CISG or to which the parties have made the CISG applicable.

(10) Duty to avoid damages. -- There is a broad agreement that the CISG contains the general obligation of the parties to avoid damages to the other party as far as reasonable.[57] This legal thought is to be found in Art. 77 CISG. The provision contains an obligation of the party claiming damages to keep these damages to a minimum. In addition, Articles 85 and 86 CISG establish -- for the party who is in possession of goods which have to be returned to the other party -- a separate duty to preserve the goods under certain circumstances. These provisions are based on the thought, which can be generalized, that the party who pursuant to the contract has actual possession over the goods of the other party is obligated to exercise reasonable care and avoid damages. Accordingly, the duty to preserve the goods under Art. 85 CISG should not only apply to the goods, but also, e.g., to material furnished by the buyer.[58]

(11) General duty to cooperate. -- The commentators further derive from the CISG a general duty of the parties to cooperate.[59] This duty is deduced from the duties provided in the CISG in addition to the central performance obligations of the parties: from the duty to preserve goods to be returned which has just been explicated above (Art. 85/86), the extensive duty to accept cure (Arts. 34, 37, 48), the duty to avoid damages (Art. 77), the numerous direct or indirect[60] duties to notify the other party.[61] These duties as well as Arts. 32 and 60 CISG can be interpreted to express the general principle that every party is obligated to enable the other party to perform and not to jeopardize the contractual purpose.[62] In addition, some commentators assume a general duty to inform the other party.[63] However, since the duties to notify the other party are regulated in great detail (see note 61), it appears doubtful whether an additional, broader general duty to inform the other party exists. For reasons of clarity of the legal situation the parties should be able to determine directly from the CISG when they are obligated to give what information.[64]

(12) Duty to pay damages. -- The CISG is based on the general structural principle that every party has to pay damages incurred by the other party due to a breach of contract in full, unless there is a ground for exemption (Art. 79). Basically, this principle can be derived as a direct rule from Art. 45(1)(b) and Art. 61(1)(b) in conjunction with Art. 74 et seq. CISG, which applies in case of breach of any obligation resulting from the contract or the Convention. Yet, this rule also constitutes a general principle which is valid even in cases of additionally stipulated or implied further obligations of the parties.

(13) Concurrent performance. -- Although it is not clearly emphasized as a principle, Art. 58(1) CISG can be interpreted to include the rule that the parties, absent an agreement to the contrary, are only obligated to render their performances concurrently.[65] Thus, no party is obligated to perform first.[66] However, the buyer must have had an opportunity to examine the goods (external, cursory inspection) before his payment is due (Art. 58(3) CISG).

In addition, concurrent performance is stipulated for restitution upon contract avoidance (Art. 81(2), second sentence CISG). Therefore, the principle of concurrent performance -- as a characteristic element of synallagmatic contractual relationships -- has to apply generally to the parties' obligations to perform. Thus, also with regard to additional services the parties agreed upon (e.g., installation) the rule results that in case of doubt payment is due only upon completion of the entire performance (e.g., installation).

(14) Set-off of claims arising under the Convention. -- Set-off is not regulated in the CISG. In general, it is governed by the law applicable by virtue of the rules of private international law.[67] However, quite often the claims subject to set-off are claims which result from the contractual relationship governed by the CISG. The main example is a claim to pay damages, which the buyer wants to set off either wholly or in part against the seller's payment claims because the goods were nonconforming and have caused damage. In this case a set-off should be granted directly by virtue of the CISG.[68] At least indirectly such a set-off is provided also in the CISG itself, specifically in Art. 84 (2) CISG in the event that the buyer has to account to the seller for all the benefits which he has derived from the goods to be returned and may demand a refund of the price. The principle of concurrent performance explicated in the previous paragraph also speaks for a set-off of payment claims arising under the Convention, without any further requirements and without recourse to private international law. This should be the case even if the currency of the payment claims arising under the Convention should not be the same, because a conversion as of a certain date (regularly the date the set-off took effect) should always be possible.[69]

(15) Retention right. -- From the principle of concurrent performance we may conclude that in case of doubt a party may hold back on her performance until the other party offers her performance in conformity with the contractual terms. In addition, in case of justified doubts about the other party's performance Art. 71 grants the right to suspend performance (paragraph 1) or -- only for the seller -- the right to stop the goods during their transport to the buyer (paragraph 2). From these provisions we can derive the general rule that -- except for the situations just mentioned -- there are no retention rights under the CISG. Again, in that respect there is no need for recourse to the rules of private international law. The conflict rules are to be employed only if a party wants to exercise a retention right as against obligations under the Conventions that result from other rights not governed by the CISG.[70]

(16) Passing of risk only in case of identification of the goods to the contract. -- As already mentioned above[71], Articles 67(2) and 69(3) CISG provide that risk does not pass unless the goods are clearly identifiable to a specific contract. Although Art. 68 (passing of risk in case of goods sold in transit) does not contain this rule, as a general principle it has to apply also to this case and similar situations.[72]

(17) Passing of encumbrances and benefits with passing of risk. -- The CISG does not contain a general rule as to the date from which the buyer is entitled to draw benefits from the goods and has to bear their encumbrances. However, in that respect the basic rule regarding the passing of risk can be utilized. In case of doubt the time when risk passes is also relevant for the passing of benefits and encumbrances.[73]

(18) Calculation of time limits. -- Pursuant to Art. 20(2), official holidays or non-business days generally do not extend the period for acceptance, unless a notice of acceptance cannot be delivered on the last day of the period because that day falls on an official holiday or a non-business day. This thought can be applied analogously to similar cases. It can also be used to calculate other periods -- e.g., the period for performance, payment etc. -- which are also extended if the performance, payment etc. is impossible on the last day of the period because this day is an official holiday or a non-business day.[74] Recourse to the applicable national law regarding calculation of time limits cannot be taken in that respect.[75]

(19) Theory of dispatch. -- Article 27 CISG declares the theory of dispatch relevant for Part III of the Convention: Declarations or notices are effective upon (timely) dispatch. Their receipt is only necessary if expressly required by the Convention. This principle has to be extended to Part II of the CISG (conclusion of contracts). However, the Convention expressly demands receipt in order for an offer or an acceptance and also other declarations to be effective (see, in particular, Arts. 15, 18 (2)). Yet, in conformity with the general principle, declarations pursuant to Art. 21 (notices regarding late acceptance) require only dispatch to be effective.[76]

(20) Theory of receipt. -- Art. 24 defines receipt as far as it is required for declarations under the CISG; however, this definition refers expressly only to Part II of the Convention. All agree that the definition is of general relevance -- and thus also for Part III of the CISG.[77] If, for example, Art. 47(2), 48(4), 63(2), 65(1) and (2), 79(4) require that the other party has "received" a notice, Art. 24 applies by way of analogy.[78]

(21) Maturity without request. -- Pursuant to Art. 59 CISG payment of the purchase price is due on the date fixed for payment. The CISG does not require any request or other formality. This rule is to be regarded as a general principle which also applies to other payment claims -- e.g., repayment, damages, reimbursement for expenses, and interest.[79]

(22) Imputation of third party conduct and knowledge. -- Quite often the question arises in which cases actual conduct or knowledge of third persons has to be imputed to a party; e.g., whether a declaration has been received if it has been delivered to an employee of the other party to the contract; further, whether the knowledge of an employee or other person acting on behalf of a party regarding lack of conformity of the goods or title defects has to be imputed to the party, etc. While the imputation of actions constituting a legal transaction is governed by the national law applicable to agency issues[80], with respect to imputation of conduct and knowledge we can extract a general rule from Art. 79 (2) in conjunction with (1) CISG. The provision expresses -- beyond its wording -- that a party will be imputed the conduct and knowledge of her own people and such third persons "whom she has engaged to perform the whole or a part of the contract" (Art 79(2)).[81]

(23) Currency. -- The majority of the commentators -- in my opinion correctly -- derive from the CISG the general principle that in case of doubt payment of the purchase price has to be made in the currency at the seller's place of business.[82] What speaks for this solution[83] -- in addition to the need for a uniform legal solution -- is the fact that the CISG in relation to payment shows a certain preference for the creditor. For example, payment has to be made at the creditor's place of business (Art. 57(1)(c)) and the buyer has to comply with any payment formalities existing at that place (Art. 54 CISG).

(24) Place of performance for payment claims. -- Article 57 determines that in case of doubt payment of the purchase price has to be made at the seller's place of business. From this rule we can infer the general principle that, in case of doubt, the place of performance also with respect to other payments (repayment, reimbursement for expenses, interest, also liquidated damages etc.) is the creditor's place of business.[84] However, the place for payment of damages is controversial.[85]

(25) Interest. -- From Arts. 78 and 84(1) results the general principle that a sum due under the CISG bears interest from the date it is due.

(26) Burden of proof. -- A clear majority of the commentators now holds that the CISG also contains -- or allows deduction of -- rules regarding the burden of proof as general principles.[86] The Convention itself provides explicitly for a specific distribution of the burden of proof in Art. 79(1) CISG: A party will only be exempt from its obligation to perform "if he proves" that there is a ground for exemption. In addition, the wording of several provisions allows one to conclude a specific distribution of the burden of proof. For example, use of the term "unless" ("à moins que")[87] indicates that the burden of proof lies with the party asserting the "unless" exception.[88] Finally, some provisions practically presuppose a certain distribution of the burden of proof: Only the party asserting a reasonable excuse for a defective notice pursuant to Art. 44 CISG can bear the burden of proof in that respect; similarly, the burden of proof for the contents of a declaration that was only partially or not at all received (in the context of Art. 26) has to be on the party who made the declaration.

Three general principles regarding the burden of proof can be derived from the relevant provisions as a whole:

(a) Each party generally has to prove the existence of the factual prerequisites contained in the legal provision from which that party wants to derive beneficial legal consequences.[89]

(b) The party asserting an exception in her favor generally has to prove the existence of the factual prerequisites of that exception.[90]

(c) Facts lying in a party's own sphere of responsibility and therefore better known to that party have to be proven by the party exercising control over that sphere.[91]

c) Rules not to be interpreted as general principles

(1) Interest rate. -- Only a few -- yet important -- commentators hold that the interest rate left open in Art. 78 CISG can be derived from general principles underlying the CISG.[92] However, according to a vast majority in commentary and jurisdiction, this opinion has to be rejected.[93] The Convention itself does not contain any indication of a standard for the interest rate. In any event, a relevant national law -- e.g., the law applicable at the creditor's place of business -- would have to be taken into account. In this case, however, utilization of the rules of private international law is the appropriate procedure.

(2) Seniority of payment claims. -- Dutch courts have derived the general principle from the EKG that in case of doubt payments are first to be applied to interest, then to the oldest outstanding debt.[94] Yet, the CISG -- like the EKG -- does not contain a provision indicating this thought, even if such a regulation appears practical and may correspond to the hypothetical intention of the parties. Therefore, this seniority of payment claims cannot be regarded as a general principle.[95]

d) Analysis

On closer examination it appears that there no longer is only a small number of general principles on which a considerable majority agrees. Also, the general principles are not restricted to rules of such a general nature that we cannot expect them to be of any use for the decision-making process in specific cases. In my opinion, the determined principles do not specifically refer to sales law issues. Probably all these principles could also be included in other Conventions regarding the international unification of contracts. Even if the principles described here are based on the structures and legal concepts of the CISG, they appear to be subject to generalization and express concepts of the basics of bilateral contracts in general. Therefore, it is no coincidence that the preponderant part of these principles is to be found both in the principles of international lex mercatoria[96] as well as in the UNIDROIT principles described below.

6. The UNIDROIT-Principles

a) Origin and objective

After several years of preparation[97], UNIDROIT published "Principles of International Commercial Contracts" in 1994.[98] The "Principles" have been developed on a broad comparative law basis by a working group consisting of internationally renowned lawyers from the member states represented in UNIDROIT. Probably all the important legal systems were represented in that group, which was headed by the Italian Michael Joachim Bonell.[99]

The "Principles" go a path new to international comparative legal analysis. Two points in particular have to be highlighted: First, the legal instrument used is new. The "Principles" create neither direct substantive uniform law nor an international model law which is to be accepted or rejected in toto, but compile a set of rules which is intended to serve as a guideline for regulation and a model in three different contexts: as a model for legislation on a national and international level; as a guideline for interpretation and filling of gaps with respect to international Conventions or in case the applicable law cannot be determined; and as an aid for the parties to international commercial contracts when drafting and performing their contracts. However, the "Principles" are legally binding only if the parties stipulated their applicability.[100]

Second, the method of developing the "Principles" is new: The principles constitute neither a "Restatement" of the common principles of all or only the most important legal systems nor standard industry terms. Rather, they result from the attempt to derive principles from the common features, which are reasonable from a practical and theoretical perspective, of a selected set of legal systems, i.e. the modern[101] ones, as well as from important Conventions such as the CISG and international sets of terms such as Incoterms, etc.[102]

Overall, the "Principles" attempt to meet the criticism of international legislation to unify law described above (under 1.) and to create a more flexible, adaptable instrument than a Convention or a Model Law.[103]

b) Application of the "Principles" as general principles within the framework of the CISG?

As discussed above, Art. 7(2) CISG allows utilization of the general principles, on which the Convention is based and which merely haven't been expressed directly, for the purpose of filling gaps. In general, any general principles existing outside of the CISG are not to be considered. Is that also true for the "Principles"? As seen above, their authors, among other things, have designed the "Principles" for the purpose of providing a guideline for interpretation and for filling gaps in international Conventions regarding commercial contracts.[104] To be sure, this intention alone cannot suffice. In addition, the selective approach in developing the "Principles" may give rise to concern.

However, in my opinion the "Principles" are nevertheless to be considered as additional general principles in the context of the CISG. The most important reason for this is that they vastly correspond both to the respective provisions of the CISG as well as to the general principles which have been derived from the CISG.[105] In light of the fact that the CISG basically was the force behind the "Principles", this correspondence is not surprising.

Further, the approach in developing the "Principles" appears appropriate with respect to the current state of attempts to unify law. The CISG provides a basic set of rules which has resulted from an intensive comparison of legal systems and politically supported compromises between these legal systems. Therefore, the CISG can and should constitute the basis for the creation of a general law of contracts. Its provisions are to be generalized only to supplement new issues and solutions and align these issues and solutions with the needs of the industry. The UNIDROIT working group has proceeded with this concept in mind. Thus, its results, to the extent that they formulate general principles which cannot be derived directly from the CISG, can be utilized for filling gaps in the Convention.[106]

7. Conclusion

In 1970, Kötz -- in continuation of Zweigert's[107] ideas -- has requested that the general principles are applied as a substitute if the law applicable by virtue of the rules of private international law cannot be determined.[108] This "theory makes especially great demands on the judge".[109] Yet, the [then] current state of comparative law and the increasing number of international legal transactions allowed and required "maybe not yet for the situation today, but definitely for the near future"[110] to entrust the respective judge with the task to determine general legal principles based on a comparative legal analysis and to render his decision accordingly. A quarter-century later, the situation existing then has hardly changed. General principles derived from comparative legal analysis, according to which disputes of whatever nature can generally be settled and which -- at the same time -- guarantee the predictability of legal decisions, are available only to a very limited extent.[111] It already appears as a significant step forward if at least for a specialty area like the law of the international sale of goods we can determine a set of recognized general legal principles. The possibility to generalize this set of principles as well as the UNIDROIT-Principles nurture a certain optimism that in the not too far future common general legal principles at least for international commercial contracts will be developed and accepted.

FOOTNOTES

* Abbreviated citations are being used for: Audit, La vente internationale de marchandises, Convention des Nations Unies du 11 avril 1980 (1990); Bianca/Bonell, Commentary on the International Sales Law, The 1980 Vienna Sales Convention (1987); Bonell, An International Restatement of Contract Law, The UNIDROIT Principles of International Commercial Contracts (1994) (cited as: Restatement); v. Caemmerer/Schlechtriem, Kommentar zum Einheitlichen UN-Kaufrecht, Das Übereinkommen der Vereinten Nationen über Verträge über den internationalen Warenkauf-CISG-Kommentar² (1995); Enderlein/Maskow/Strohbach, Internationales Kaufrecht, Kaufrechtskonvention, Verjährungskonvention, Vertretungskonvention, Rechtsanwendungskonvention (1991) (review by Reinhart, RabelsZ 58 [1994] 136 et seq.); Herber/Czerwenka, Internationales Kaufrecht, Kommentar zu dem Übereinkommen der Vereinten Nationen vom 11. April 1980 über Verträge über den internationalen Warenkauf (1991); Honnold, Uniform Law for International Sales Under the 1980 United Convention² (1991); Karollus, UN-Kaufrecht, Eine systematische Darstellung für Studium und Praxis (1991) (review by Magnus, RabelsZ 59 [1995] 147 et seq.); Neumayer/Ming, Convention de Vienne sur les contrats de vente internationale de marchandises, Commentaire (1993); Piltz, Internationales Kaufrecht, Das UN-Kaufrecht (Wiener Übereinkommen von 1980) in praxisorientierter Darstellung (1993) (review by Reinhart [this note]); Reinhart, UN-Kaufrecht, Kommentar zum Übereinkommen der Vereinten Nationen vom 11. April 1980 über Verträge über den internationalen Warenkauf (1991) (review by Honsell, RabelsZ 57 [1993] 335 et seq.); Schlechtriem/Magnus, Internationale Rechtsprechung zu EKG und EAG, Eine Sammlung belgischer, deutscher, italienischer, israelischer und niederländischer Entscheidungen zu den Haager Einheitlichen Kaufgesetzen (1987) (1987) (review by Posch, RabelsZ 54 [1990] 182); Soergel(-Lüderitz), Kommentar zum Bürgerlichen Gesetzbuch I¹² (1991); Staudinger(-Magnus), Wiener UN-Kaufrecht (CISG) (1994); further: United Nations Conference on Contracts for the International Sale of Goods, Vienna 10 March -- 11 April 1980, Official Records UN DOC. A./CONF. 97/19 (cited as: Off. Rec.).

1. H. Kötz, Rechtsvereinheitlichung -- Nutzen, Kosten, Methoden, Ziele: RabelsZ 50 (1986) 1 et seq. (3); H. Kötz, Europäische Juristenausbildung: ZEuP 1 (1993) 268 et seq.; see also M.H. Bonell, Restatement 10; H.-J. Mertens, Nichtlegislatorische Rechtsvereinheitlichung durch transnationales Wirtschaftsrecht und Rechtsbegriff: RabelsZ 56 (1992) 219 et seq. (221).

2. Kötz, Rechtsvereinheitlichung 5; Kötz, Europäische Juristenausbildung 269 (both previous note).

3. Kötz, Rechtsvereinheitlichung (above note 1) 7.

4. See Projet de Code des Obligations et Contrats (1929).

5. See for the (old) Nordic Sales Law T. Almén, Das Skandinavische Kaufrecht, German edition by F.K. Neubecker, I-III (1922); for the current situation L. Sevón, The New Scandinavian Codification on the Sale of Goods and the 1980 United Nations Convention on Contracts for the International Sale of Goods, in: Einheitliches Kaufrecht und nationales Obligationsrecht, published by Schlechtriem (1987) 343 et seq. (cited as: Einheitliches Kaufrecht); in general G. Carsten, Europäische Integration und nordische Zusammenarbeit auf dem Gebiet des Zivilrechts: ZEuP 1 (1993) 335 et seq.

6. United Nations Convention on Contracts for the International Sale of Goods of April 11, 1980, BGB1. 1989 III 588; hereinafter cited as CISG.

7. E.g., the relationship between the CISG and general contract avoidance due to error or the law of torts; see in more detail v. Caemmerer/Schlechtriem(-Herber) Art. 4 notes 13, 23, Art. notes 4 et seq.; Staudinger(-Magnus) Art. 4 notes 48 et seq., Art. 5 notes 11 et seq.

8. One only has to compare the doubts raised in the commentaries regarding Art. 4 and 5 CISG.

9. (2) Les questions concernant les matières régies par la présente Convention et qui ne sont pas expressément tranchées par elle seront reglées selon les principes géneraux dont elle s'inspire ou, à défaut de ces principes, conformément à la loi applicable en vertu des règles du droit international privé.

10. See Art. 6(2) Convention on Agency in the International Sale of Goods of February 17, 1983 (published in: Rev. dr. uniforme 1983 I-III, 133/137); Art 6(2) Convention on International Financing Leasing of May 22, 1988 (published in: RabelsZ 51 [1987] 730); Art. 4(2) Convention on International Factoring of May 28, 1988 (published in: RabelsZ 53 [1989] 733).

11. The draft is published in: RabelsZ 9 (1935) 8.

12. E. Rabel, Der Entwurf eines einheitlichen Kaufgesetzes: RabelsZ 9 (1935) 1 et seq. (54).

13. Wording of Art 11 E 1935 and Rabel (previous note) 55.

*. Translator's note: Einheitliches Gesetz über den internationalen Kauf beweglicher Sachen [(German) Uniform Law on the International Sale of Goods].

14. Dölle(-Wahl), Kommentar zum Einheitlichen Kaufrecht, Die Haager Kaufrechtsübereinkommen vom 1. Juli 1964 (1976) Art. 17 notes 75 et seq.; R.H. Graveson/E.J. Cohn/D. Graveson, The Uniform Laws on International Sales Act 1967 (1968) 62.

15. Dölle(-Wahl) Art. 17 notes 75 et seq.; Graveson/Cohn/Graveson (both previous note).

16. H.-J. Mertens/E. Rehbinder, Internationales Kaufrecht, Kommentar zu den Einheitlichen Kaufgesetzen (1975) Art. 17 notes 5 et seq.

17. E.g., the principle of good faith: OLG Düsseldorf January 20, 1983, in: Schlechtriem/Magnus Art. 17 No. 7; the principle of reasonableness: Hof Amsterdam January 5, 1978, S & S 1978, 79; the prohibition against abuse: OLG Karlsruhe July 25, 1986, RIW 1986, 818; further the principle that the place of performance for payment as well as repayment of the purchase price is the seller's place of business: BGH October 22, 1980, BGHZ 78, 257; the principle that, in case of doubt, payments have to be applied first to interest on default, then to the oldest outstanding debt: Rb. Alkmaar May 27, 1982, in: Schlechtriem/Magnus Art. 17 No. 4; Hof Amsterdam November 4, 1982, Ned. IPR 1983 No. 215; the principle that the law of the seller is applicable to issues of prescription: OLG Schleswig-Holstein April 8, 1992, RIW 1992, 582; the principle that in case of doubt the payment has to be made in the currency at the creditor's place of business: OLG Koblenz January 21, 1983, in: Schlechtriem/Magnus Art. 17 No. 8; and finally the principle that the theory of complete restitution applies to compensation for damages: BGH November 28, 1990, NJW 1991, 639 (640).

18. See for the transfer of rights (OLG Hamm July 1, 1982, in: Schlechtriem/Magnus Art. 17 No. 5), the Ordinance (OLG Koblenz March 1, 1985, Art. 17 No. 11), the liability for third parties (BFH March 14, 1984, NJW 1984, 2034; OLG Hamm December 19, 1983, Art. 40 No. 7) and the setoff (AG Frankfurt January 31, 1991, IPRax 1991, 345).

19. See UNCITRAL Yb. 1 (1968--70; published: 1971) 159 (170 et seq.); UNCITRAL Yb. 2 (1971; published: 1972) 37 (49 et seq.).

20. Off. Rec. 87.

21. Art. 6 Agency Convention of 1983; Art. 6 Leasing Convention of 1988; Art. 4 Factoring Convention of 1988 (all above note 10).

22. Karollus 16.

23. See above under 3.

24. See Rabel (above note 12); but Neumayer/Ming Art. 7 note 7.

25. In case of doubt the English version (above note 9) is of particular importance, because English was the language of the preliminary drafts and deliberations in Vienna. In addition, the Spanish version of Art. 7(2) CISG corresponds to the English version: "en los que se basa".

27. Generally, in favor of a certain"creative development" of the CISG Enderlein/Maskow/Strohbach Art. 7 note 10.1; Herber/Czerwenka Art. 7 note 11.

28. Kötz, Rechtsvereinheitlichung (above note 1) 11; P. Behrens, Voraussetzungen und Grenzen der Rechtsfortbildung durch Rechtsvereinheitlichung: RabelsZ 50 (1986) 19 et seq. (26); Mertens (above note 1) 221; P.H. Neuhaus/J. Kropholler, Rechtsvereinheitlichung -- Rechtsverbesserung?: RabelsZ 45 (1981) 73 et seq. (80 et seq.).

29. Published in 1994; see in detail Bonell (above note 1).

31. So defined by H. Dölle, Bemerkungen zu Art. 17 des Einheitsgesetzes über den Internationalen Kauf beweglicher körperlicher Gegenstände, in: FS Ficker (1967) 138 et seq. (141).

32. They are regularly regarded as part of the general principles of Art. 7(2) CISG; see Bianca/Bonell (-Bonell) Art. 7 note 2.3.2.2; v. Caemmerer/Schlechtriem (-Herber) Art. 7 note 36; Herber/Czerwenka Art. 7 note 12; Reinhart Art. 7 note 7.

33. See also below 5 b (18).

34. OLG Düsseldorf July 2, 1993, RIW 1993, 845 (the place of performance for payment claims is generally the creditor's place of business); implicitly also KG January 24, 1994 (RIW 1994, 683 (in case of doubt the currency at the creditor's place of business is relevant).

35. See Neumayer/Ming Art. 7 note 7.

36. See, e.g., Audit 51 et seq.; Bianca/Bonell(-Bonell) Art. 7 note 2.3.2.2; v. Caemmerer/Schlechtriem (-Herber) Art. 7 notes 33 et seq.; Enderlein/Maskow Art. 7 note 9.1 et seq; Enderlein/Maskow/Strohbach Art. 7 note 9.1 et seq.; Herber/Czerwenka Art. 7 note 11; Honnold, Uniform Words and Uniform Application, in: Einheitliches Kaufrecht (above note 5) 115 et seq. (139); Karollus 16 et seq.; Staudinger/Magnus Art. 7 notes 41 et seq.

37. A compilation of these principles was prepared by Mustill, The New Lex Mercatoria, The First Twenty-five Years: Arb. Int. 4 (1988) 110 et seq.:

1. Pacta sunt servanda

2. In case of contracts requiring continous or recurring performance the clausula rebus sic stantibus (requirement that the material circumstances on which the contract is based remain unchanged -- no frustration of contract) is applicable as an exception to 1.

3. As an exception to 1., abuse is prohibited and unreasonable contracts and provisions are not enforceable.

4. Liability for culpa in contrahendo is recognized.

5. Contracts are subject to the principle of good faith.

6. Contracts obtained by fraud or other dishonest means are void or not enforceable.

7. State-owned companies cannot avoid their contractual obligations by claiming domestic restrictions of their ability to enter into obligations in arbitration proceedings.

8. The entity which holds the controlling interest in a group of companies can enter into valid contracts, at least arbitration agreements, for each single company.

9. If unforeseeable events impede contract performance, the parties should re-negotiate in good faith even if the contract does not contain a revision clause.

10. Gold clauses are valid and enforceable and sometimes have to be -- along with "hardship"-clauses --implied in the contract.

11. A party is entitled to contract avoidance if the other party has committed a fundamental breach of contract.

12. No party may make her performance impossible through her own conduct.

13. A court is not bound by the parties' classification of the contract.

14. Damages for breach of contract are restricted to the foreseeable consequences of the breach.

15. The aggrieved party has to take reasonable steps to mitigate damages.

16. Damages for failure to deliver are calculated in accordance with the market price and the price for substitute goods obtained.

17. A party loses her rights unless she acts fast. In general, a party has to protect her rights in a careful and practical manner.

18. Under certain circumstances a debtor may offset his own claims against his debts.

19. Contracts are to be interpreted according to the principle ut res magis valeat quam pereat (in case of doubt in favor of their validity).

20. Silence of a party with respect to written declarations of the other party constitutes acceptance of the declaration's contents.

Generally to the relationshipt between CISG and lex mercatoria Kappus, "Lex mercatoria" in Europa un Wiener UN-Kaufrechtskonvention 1980, "Conflict avoidance" in Theorie und Praxis schiedsrichterlicherund ordentlicher Rectsprechung in Konkurrenz zum Einheitskaufrecht der Vereinten Nationen (1990).

38. See, e.g., Bianca/Bonell(-Bonell) Art. 7 note 2.3.2.2; v. Caemmerer/Schlechtriem(-Herber) Art. 7 note 36; Ferrari, Uniform Interpretation of the 1980 Uniform Sales Law: Ga.J.Int.Comp.L. 24 (1994) 183 et seq. (223) (cited as: Uniform Interpretation); Herber/Czerwenka Art. 7 note 12; Hyland, Liabiltiy of the Seller for Conformity of the Goods Under the UN Convention (CISG) and the Uniform UCC, in: Einkeitliches Kaufrecht 305 et seq. (329 et seq.).

39. Mustill (above note 37) 110 lists this rule as the primary principle of international lex mercatoria.

40. Bianca/Bonell(-Bonell) Art. 7 note 2.4.1; v. Caemmerer/Schlechtriem(-Herber) Art. 7 note 7; Enderlein/Maskow/Strohbach Art. 7 note 1; Karollus 12; Staudinger(-Magnus) Art. 7 note 10; arriving at the same conclusion Ferrari, Vendita internazionale (above note 30) Art. 7 note 6; probably also Honnold note 95; reserved Loewe, Internationales Kaufrecht, Wiener UN-Kaufrechtsübereinkommen vom 11. April 1980 und New Yorker UN-Verjährungsübereinkommen vom 14. Juni 1974 samt Protokoll vom 11. April 1980 (1989) 33; Farnsworth, The Convention on the International Sale of Goods from the Perspective of the Common Law Countries, in: La Vendita Internazionale (1981) 18.

41. Audit, 51 et seq; v. Caemmerer/Schlechtriem(-Herber) Art. 7 note 17; Herber/Czerwenka Art. 7 note 6; Honnold (above note 36) 144; Piltz § 2 note 170; Staudinger(-Magnus) Art. 7 note 25.

42. See Audit 51 et seq. and Staudinger(-Magnus) Art. 7 note 25.

43. See Ferrari, Vendita internazionale (above note 30) Art. 7 note 6.

44. See, e.g., Reinhart Art. 7 note 5; partially Enderlein, Uniform Law and Its Application by Judges and Arbitrators, in: International Uniform Law in Practice (1988) 342.

45. In more detail Staudinger(-Magnus) Art. 7 note 28.

47. See, e.g., Art 16(2)(b); 18(2); 25; 33(c); 39(2); 43(1); 47; 49(2); 63(1); 64(2)(b); 65(2); 72(2); 73(2); 75; 77 first sentence; 79(1) and (4); 85 first sentence; 86(1); 88(1) and (3); also "unreasonable": e.g. in Art. 86(2); 87; 88(2).

48. Audit 51; Bianca/Bonell(-Bonell) Art. 7 note 2.3.2.2; Enderlein/Maskow/Strohbach Art. 7 note 9.1; Ferrari, Uniform Interpretation (above note 38) 224 et seq.; Honnold (above note 36) 139; Karollus 16 et seq.

49. v. Caemmerer/Schlechtriem(-Huber), Kommentar zum Einheitlichen UN-Kaufrecht (1st edition 1990) Art. 46 note 46 (no longer included in the 2nd edition); Staudinger(-Magnus) Art. 4 note 53; but Frigge (above note 26) 82 and -- regarding the EKG -- Soergel(-Lüderitz) Art. 8 EKG note 8.

50. See above under (4).