MLA

Great Britain. War Office. General Staff. Geographical Section, United States. Army Map Service. Cape Verde Archipelago. U.S. Army Map Service, 1943. https://collections.library.yale.edu/catalog/15238414.

APA, 6th edition

Great Britain. War Office. General Staff. Geographical Section, U. S. A. M. S. (1943). Cape Verde Archipelago. [Maps]. U.S. Army Map Service, https://collections.library.yale.edu/catalog/15238414.