This article does not encompass the entire subject of foreign taxation but is limited to two specific questions involved therein: 1. Where does a sale take place for purposes of Federal Taxation? 2. If it is determined that the sale takes place partly within and partly without the U. S., how much of the income from such sales is taxable to the U. S.?
Marvin I. Kelner & Lloyd J. Fingerhut, Puerto Rico - Tax Haven or Tax Trap, 8 Clev.-Marshall L. Rev. 375 (1959)