Cite

[Photograph of two men securing pack on horse]

MLA

[Photograph of Two Men Securing Pack on Horse]. 1915. https://collections.library.yale.edu/catalog/11683460.

APA, 6th edition

[Photograph of two men securing pack on horse]. (1915). [Photographs, Slides (glass)]. https://collections.library.yale.edu/catalog/11683460.