MLA
Hess, Fred, and Son. Men in Uniforms, Some on Horses, with Boy Scouts. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 49. https://digital.library.emory.edu/purl/56341ns1wt-cor.
APA, 6th edition
Hess, F., & S. Men in uniforms, some on horses, with boy scouts (Box 49) [Card photographs (photographs)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/56341ns1wt-cor.
Chicago
Hess, Fred, and Son. “Men in Uniforms, Some on Horses, with Boy Scouts.” Card photographs (photographs). Robert Langmuir African American Photograph Collection, n.d. Box 49. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/56341ns1wt-cor.