APA (7th ed.) Citation

United States. Army. Air Corps. (1920). Regulations for Corps Air Service operations officers, including description of divisional corps observation operations room. U.S. GPO.

Chicago Style (17th ed.) Citation

United States. Army. Air Corps. Regulations for Corps Air Service Operations Officers, Including Description of Divisional Corps Observation Operations Room. Washington: U.S. GPO, 1920.

MLA (9th ed.) Citation

United States. Army. Air Corps. Regulations for Corps Air Service Operations Officers, Including Description of Divisional Corps Observation Operations Room. U.S. GPO, 1920.