Cite

Photograph of the Windsor building, Denver, Colorado [graphic].

MLA

Jackson, William Henry, 1843-1942. Photograph of the Windsor building, Denver, Colorado [graphic].. ca 1890.. https://collections.library.yale.edu/catalog/2011180.

APA, 6th edition

Jackson, William Henry, 1843-1942. (ca 1890.)[Photograph of the Windsor building, Denver, Colorado [graphic].]. https://collections.library.yale.edu/catalog/2011180.