MLA

Staff, United States. War Dept. General. Strategical Map of Part of Korea and Manchuria / Prepared by the Second Division, General Staff (Military Information Division), War Department. Second Division, General Staff, 1906. https://collections.library.yale.edu/catalog/15827218.

APA, 6th edition

Staff, U. S. W. D. G. (1906). Strategical map of part of Korea and Manchuria / prepared by the Second Division, General Staff (Military Information Division), War Department. [Maps]. Second Division, General Staff, https://collections.library.yale.edu/catalog/15827218.