United States. War Department. (1932). Infantry and aircraft armament: Browning machine gun, caliber .50, M1921, water-cooled. GPO.
Chicago Style (17th ed.) CitationUnited States. War Department. Infantry and Aircraft Armament: Browning Machine Gun, Caliber .50, M1921, Water-cooled. [Washington]: GPO, 1932.
MLA (9th ed.) CitationUnited States. War Department. Infantry and Aircraft Armament: Browning Machine Gun, Caliber .50, M1921, Water-cooled. GPO, 1932.
Warning: These citations may not always be 100% accurate.