Shantou Real Lingerie Manufacturing Company (Shantou) is incorporated in China. Shantou manufactures and exports garments to the United States. Native Group International, Inc. (Native), is a corporation organized under the laws of New York engaged in the business of selling intimate wear to the wholesale and retail market. Between May and November 2013, Native placed dozens of orders with Shantou for lingerie. Following each order, Shantou issued a sales confirmation to Native, which referenced the cost, quantity, and type of goods ordered. These confirmations were signed by a representative of Native. Thereafter, Shantou manufactured the goods in accordance with the requested specifications. Between October 2013 and February 2014, Shantou delivered the goods specified in the confirmations to Native through five separate shipments. Shantou also included in each of the five shipments an invoice, indicating the total balance due, as well as the price, quantity, and type of products shipped. Native accepted each shipment, retained the goods delivered, and never claimed a set-off or credit. The total amount invoiced for the five shipments was $437,562.20. Native made payments totaling $165,522.80, leaving an unpaid balance of $272,040.40. The communications between Shantou and Native were silent with respect to the governing law. Native claimed that there was no written contract between the parties when Shantou subsequently filed a lawsuit against Native for the unpaid balance. What law should govern the terms of the parties' arrangement? Is a written agreement necessary in this case? What are the terms of the parties' agreement if any?