MLA
Brothers., Russell. When Shall We Three Meet Again : Man Standing next to a Horse. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 1. https://digital.library.emory.edu/purl/013mw6m94x-cor.
APA, 6th edition
Brothers., R. When shall we three meet again : man standing next to a horse (Box 1) [Black-and-white photographs]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/013mw6m94x-cor.
Chicago
Brothers., Russell. “When Shall We Three Meet Again : Man Standing next to a Horse.” Black-and-white photographs. Robert Langmuir African American Photograph Collection, n.d. Box 1. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/013mw6m94x-cor.