Browning machine gun, caliber .50, M2, water cooled, and mounts - USA Voorschrift, Technical Manual, 9-226 Browning machine gun, caliber .50, M2, aircraft, fixed and flexible - USA Voorschrift, Technical Manual, 9-225 Browning machine gun, caliber .50, HB, M2 ground - USA Basic Field Manual, FM 23-60 Browning machine gun caliber .30, HB, M1919A4 (mounted in combat vehicles) - USA Basic Field Manual, FM 23-50 Browning machine gun, caliber .50 HB, M2 / War Department - USA Field Manual, FM 23-65 Browning machine gun, caliber .30, HB M1919A4, ground - USA Basic Field Manual, FM 23-45 Browning machine gun, caliber .30, HB, M1919A4, ground - USA Basic Field Manual, FM 23-45 Browning Machine Guns, Caliber .30 inch, M1917A1, M1919A4, and M1919A6 - USA Voorschrift, Field Manual, 23-55
