APA (7th ed.) Citation

United States. Postmaster General & Clark, G. R. (1929). George Rogers Clark commemorative stamp. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Postmaster General and George Rogers Clark. George Rogers Clark Commemorative Stamp. Washington: U.S. GPO, 1929.

MLA (9th ed.) Citation

United States. Postmaster General and George Rogers Clark. George Rogers Clark Commemorative Stamp. U.S. GPO, 1929.

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