Cite

[No. 86: Photograph of two men with horses negotiating deadfall]

MLA

[No. 86: Photograph of Two Men with Horses Negotiating Deadfall] . 1915. https://collections.library.yale.edu/catalog/11680429.

APA, 6th edition

[No. 86: Photograph of two men with horses negotiating deadfall] . (1915). [Photographs, Slides (glass)]. https://collections.library.yale.edu/catalog/11680429.