APA (7th ed.) Citation

United States. Postmaster General. (1922). Special-delivery stamp, new design, 1922. [publisher not identified].

Chicago Style (17th ed.) Citation

United States. Postmaster General. Special-delivery Stamp, New Design, 1922. Washington: [publisher not identified], 1922.

MLA (9th ed.) Citation

United States. Postmaster General. Special-delivery Stamp, New Design, 1922. [publisher not identified], 1922.

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