20.O22 [Mascot Corners to Greig Junction, Houthulst Forest Southeast of Nachtegaal] December 26, 1917
Covers an area equivalent to portions of squares O22, 23, and 29 on the corresponding WWI map sheet 20. Negative roll 9B, photo 219. Annotations on recto: north arrow pointing slightly to the left of straight up. WWI Aerial Photograph Collection: Box 1, Envelope 80.