GSGS series 4414. Sheet 2911, Second Edition (A.E.F.). First edition copied from German Topographische Karte 1:25,000 Sheet 2911 dated 1934 and photolithograpged by the British Ordnance Survey in 1944. Second edition revised from air photographs December 1944 (I RCE). Lambert modified conical orthomorphic projection. Nord de Guerre Grid.