A manufacturer based in Argentina and an importer based in New Jersey entered into an oral agreement under which the importer agreed to sell the manufacturer's products in the United States. The district court found that the manufacturer's claim that the importer had failed to pay the full amount due was barred by the United Nations Convention on Contracts for the International Sale of Goods (CISG) because the agreement was not in writing. Although the CISG eliminated formal writing requirements for contracts, Argentina had made a declaration opting out of that provision. However, the United States had not made such a declaration. The court of appeals held that it was necessary to consider New Jersey choice-of-law rules to determine whether New Jersey or Argentine form requirements governed the manufacturer's claim. Does the contract need documentation to be enforceable, or, if U.S. law applies with the adoption of the CISG, are the oral declarations satisfactory?