APA (7th ed.) Citation

United States. Army. Signal Corps. (1922). Elements of automatic telephone system. GPO.

Chicago Style (17th ed.) Citation

United States. Army. Signal Corps. Elements of Automatic Telephone System. [Washington]: GPO, 1922.

MLA (9th ed.) Citation

United States. Army. Signal Corps. Elements of Automatic Telephone System. GPO, 1922.

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