Field Artillery : Tactical Employment - USA Field Manual, FM 6-20 Field artillery : Gunnery - USA Field Manual, FM 6-40 Enemy Equipment. Part 1: German Mines and Traps - Engeland Voorschrift 26/GS Publications/997 WO 8007 German Weapons Illustrated - Engeland Voorschrift 26/GS Publications/1179 Periodical Notes on the German Army no. 38 : XI Air Coprs and the attack on Crete - Engeland Voorschrift 26/GS Publications/667