Series Number Id: UNKNOWN. Sheet number: parts of sheet 57c NE, SE and 57b NW, SW. Edition number: 1. "Special sheet." Trench map and enemy organisation map. "Enemy organisation 15-9-17" in black. "Detail and trenches revised to 5-9-17" in red. "Approximate British Front Line 15-9-17" in black. Detail, contours and grid grey. "Field Survey Co., 10037"., Location: Research Collections; Fonds: WW1 Trench Maps: France; Box number: PC24; envelope_number: 725.
