training manual Topography and surveying / War Department : Map and aerial photograph reading / War Department training regulations Topography and surveying / War Department : Map and aerial photograph reading / War Department voorschrift Luchtfotolezen / vastgesteld bij aanschrijving van de Minster van Oorlog, d.d. 10 maart 1954, Hoofdkwartier van de Generale Staf, BCV nr 2289 DG g.s. publication interpretation of air photographs 1943
