A.M.S. (Series) ; L751. "Sixth Edition AMS (FEC)". Transverse Mercator projection. "Prepared by the Army Map Service (AMNS), Corps of Engineers, U.S. Army, Washington, D.C. Redrawn in 1950 from Korea 1:50,000, Japanese Imperial Land Survey, Kap'yŏng, 1939.... Aerial photography Mar., Oct. 1947.... Road classifications revised in May 1951 by the 64th Engineer Base Topographic Battalion from reconnaissance material furnished by the Engineer, EUSAK. Road classification revised in September 1951 by the 64th Engineer Base Topographic Battalion from reconnaissance material furnished by the Engineer, EUSAK." "Sino-Korean place name characters added in 1951 by 64th Engineer Base Topographic Battalion."