Cite

Part of south western Colorado [cartographic material] / U.S. Geographical Surveys West of the 100th Meridian.

MLA

Geographical Surveys West of the 100th Meridian (U.S.). Part of south western Colorado [cartographic material] / U.S. Geographical Surveys West of the 100th Meridian.. BRBL_00587. [1878]. https://collections.library.yale.edu/catalog/15824426.

APA, 6th edition

Geographical Surveys West of the 100th Meridian (U.S.). (["BRBL_00587"])([1878])[Part of south western Colorado [cartographic material] / U.S. Geographical Surveys West of the 100th Meridian.]. https://collections.library.yale.edu/catalog/15824426.