Aerial photography : Optics training regulations Topography and surveying / War Department : Aerial photographic mapping / War Department war department technical manual Aerial phototopography / War Department Vliegerkruis met persoonlijke papieren en foto's van P.L. Zeijdel (1917-1945). Drone warfare : the development of unmanned aerial conflict / Dave Sloggett Fotocamera lens, aerial Fotocamera, filter geel, aerial Diploma United States Army Air Corps Training Center Aerial Bombardiers op naam van Sergeant Paul Leo Zeijdel Vol.I V.H.F. ground station aerial systems, general and technical information: Zie AP 116E-1702-1 Aerial Attack Study, declassified version, 1964 John Boyd Variometer, aerial Aerials 100-Ft. no. 5. (Used with Wireless Sets Nos. 19, 22, 62 and 76). WO 1576 - Engeland Voorschrift