20.P31 [Six Crossroads and Kleber Crossroads, Houthulst Forest] December 18, 1917
Covers an area equivalent to portions of squares P31, and V1 on the corresponding WWI map sheet 20. Negative roll 9B, photo 168. Annotations on recto: north arrow pointing to the left. WWI Aerial Photograph Collection: Box 3, Envelope 41.