Series: GSGS 4193. Sheet number E2. Edition 1. Based on the 28Â° 59' east of Greenwich longitude Istanbul. Magnetic declination is 23 minutes east of True North for the year 1941."Copied from a map by 512 (A. Fd. Svy.) Coy. R.E., dated 1942, from black pulls dated 1941. Heliographed by O.S. 1942." Blue overwrite is to give a grid reference on the mediterranean grid. Lambert conical orthomorphic proj. Located in the Lloyd Reeds Map Collection, call no. G 7430 s200 MC51D sheet E2.