44 U.S.C. § 712

The Director of the Government Publishing Office, on receiving from the Postmaster General a copy of a postal convention between the Postmaster General, on the part of the United States, and an equivalent officer of a foreign government, shall print an accurate copy and transmit it in duplicate to the Postmaster General. On the return of one of the revised duplicates, he shall make the marked corrections and print the number specified by section 709 of this title .