MLA

Geological Survey (U.S.). Colorado (Lake County), Leadville special map [cartographic material] / triangulation and topography by A.D. Wilson, chief topographer.. 1910. https://collections.library.yale.edu/catalog/16700278.

APA, 6th edition

Geological Survey (U.S.). (1910)[Colorado (Lake County), Leadville special map [cartographic material] / triangulation and topography by A.D. Wilson, chief topographer.]. https://collections.library.yale.edu/catalog/16700278.