APA (7th ed.) Citation

United States. Postmaster General. (1928). Forms 3540 and 3548. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Postmaster General. Forms 3540 and 3548. Washington: U.S. GPO, 1928.

MLA (9th ed.) Citation

United States. Postmaster General. Forms 3540 and 3548. U.S. GPO, 1928.

Warning: These citations may not always be 100% accurate.