There are hereby exempted from the provisions of this chapter and the computation of the tax imposed by it, gross receipts resulting from the sale of agricultural and industrial production equipment in international commerce if, under the terms of the sales agreement, physical delivery of the goods takes place in South Dakota. However, the exemption only applies if written evidence of the contract of sale is retained, and such contract indicates that the goods are to be shipped in international commerce to a point outside the United States not to be returned to a point within the United States.
SDCL 10-45-93