APA (7th ed.) Citation

United States. Postmaster General. (1932). Cooperation of public in preparing Christmas mail. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Postmaster General. Cooperation of Public in Preparing Christmas Mail. Washington: U.S. GPO, 1932.

MLA (9th ed.) Citation

United States. Postmaster General. Cooperation of Public in Preparing Christmas Mail. U.S. GPO, 1932.

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