[Three Dakota Indians on horseback]
MLA
Trager, George E. [Three Dakota Indians on Horseback]. 0AD. https://collections.library.yale.edu/catalog/2038369.
APA, 6th edition
Trager, G. E. (0 C.E.). [Three Dakota Indians on horseback] [Albumen prints, Card photographs, Photographic prints, Photographs]. https://collections.library.yale.edu/catalog/2038369.