Vancouver Island / Army Map Service.
MLA
Service, United States. Army Map. Vancouver Island / Army Map Service. U.S. Army Map Service, 1943. https://collections.library.yale.edu/catalog/15536373.
APA, 6th edition
Service, U. S. A. M. (1943). Vancouver Island / Army Map Service. [Maps]. U.S. Army Map Service, https://collections.library.yale.edu/catalog/15536373.