APA (7th ed.) Citation

United States. Postmaster General. (1928). Handling franked and penalty mail. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Postmaster General. Handling Franked and Penalty Mail. Washington: U.S. GPO, 1928.

MLA (9th ed.) Citation

United States. Postmaster General. Handling Franked and Penalty Mail. U.S. GPO, 1928.

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