Arapahos.
MLA
Hutton, James D. Arapahos. 0AD. https://collections.library.yale.edu/catalog/11447599.
APA, 6th edition
Hutton, J. D. (0 C.E.). Arapahos. [Autographs, Photographic prints, Salted paper prints]. https://collections.library.yale.edu/catalog/11447599.