APA (7th ed.) Citation

United States. Postmaster General. (1932). Rate of postage on printed Christmas cards inclosed in unsealed envelopes. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Postmaster General. Rate of Postage on Printed Christmas Cards Inclosed in Unsealed Envelopes. Washington: U.S. GPO, 1932.

MLA (9th ed.) Citation

United States. Postmaster General. Rate of Postage on Printed Christmas Cards Inclosed in Unsealed Envelopes. U.S. GPO, 1932.

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