TY - BOOK PB - Office of the Surveyor General TI - A pictorial description of mapping 8 mile air navigation charts from trimetrogon air photographs KW - Photography, Aerial. A2 - Canada. Office of the Surveyor General A2 - Canada. Royal Canadian Air Force CY - Ottawa N1 - "Photographs by the Royal Canadian Air Force" PY - 1945 M1 - Accessed from https://nla.gov.au/nla.cat-vn2626650 ER -