Protection against gas and air raids : pamphlet No. 3 : passive air defence / The War Office Defence of aerodromes against air and ground attacks Passive air defence : parts I and II : issued by headquarters 21 army group air defence of Britain, 1914-1918 / Christopher Cole and E.F. Cheeseman Deci': air defence boven Middellandse Zee / door Joris Janssen Lok Foto van de controleruimte van de NATO Air Defence Ground Environment in Denemarken, oktober 1971
