4B [Scope of Convention (issues excluded): "sale of immaterial rights such as goodwill falls out of the [CISG]'s scope of application"];

64A [Seller's grounds for avoidance of contract];

81C [Obligations of parties following avoidance: restitution by each party of benefits received];

84A ; 84B [Upon avoidance: seller bound to refund price must pay interest; Buyer must account to seller for benefits received].