A.M.S. (Series) ; L751. "Fifth Edition-AMS (FEC)". Transverse Mercator projection. "Prepared under the direction of the Chief of Engineers by the Army Map Service (PT), U.S. Army, Washington, D.C. Compiled in 1946 from Korea, 1:50,000, Japanese Imperial Land Survey, Kumje, 1936; Japanese Hydrographic Charts 334, 1935.... Planimetric detail checked in 1950 from aerial photography dated 1947 by photo-planimetric methods by the 64th Engineer Base Topographic Battalion.... Universal Transverse Mercator Grid Values revised, 1950. Sino-Korean place name characters added in 1951 by the 64th Engineer Base Topographic Battalion."