This primary source comes from the Records of the Office of the Chief Signal Officer.
National Archives Identifier:
530712Full Citation: Aeroplane Graflex camera in action; ca. 1917 - 1918; Records of the Office of the Chief Signal Officer, Record Group 111. [Online Version, https://www.docsteach.org/documents/document/aeroplane-graflex-camera-in-action, April 26, 2024]