25B [Definition of fundamental breach: substantial deprivation of expectation, etc.];

49A1 ; 49B1 [Buyer's right to avoid contract (grounds for avoidance): fundamental breach; Buyer's loss of right to declare avoidance after delivery: failure to avoid within periods specified in art. 49(2)(a) and (b)];

78A [Interest on delay in receiving price or any other term in arrears]