MLA

Co, El Paso Blue Print. Map of the City of Colorado Springs and Colorado City / Compiled & Published by the El Paso Blue Print Co. El Paso Blue Print Co., 0AD. https://collections.library.yale.edu/catalog/15818436.

APA, 6th edition

Co, E. P. B. P. (0 C.E.). Map of the city of Colorado Springs and Colorado City / compiled & published by the El Paso Blue Print Co. [Maps]. El Paso Blue Print Co., https://collections.library.yale.edu/catalog/15818436.