APA (7th ed.) Citation

United States. Army. Air Corps. (1921). Topography and perspective for balloon officers. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Army. Air Corps. Topography and Perspective for Balloon Officers. Washington: U.S. GPO, 1921.

MLA (9th ed.) Citation

United States. Army. Air Corps. Topography and Perspective for Balloon Officers. U.S. GPO, 1921.

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