APA (7th ed.) Citation

United States. Postmaster General. (1926). New 3-cent postal cards, foreign single and foreign reply. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Postmaster General. New 3-cent Postal Cards, Foreign Single and Foreign Reply. Washington: U.S. GPO, 1926.

MLA (9th ed.) Citation

United States. Postmaster General. New 3-cent Postal Cards, Foreign Single and Foreign Reply. U.S. GPO, 1926.

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