MLA
Webb, L. E. African American Man Sitting on a Stool While Wearing a Suit and Hat. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 72. https://digital.library.emory.edu/purl/552w3r22bf-cor.
APA, 6th edition
Webb, L. E. African American man sitting on a stool while wearing a suit and hat (Box 72) [Photographic postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/552w3r22bf-cor.
Chicago
Webb, L. E. “African American Man Sitting on a Stool While Wearing a Suit and Hat.” Photographic postcards. Robert Langmuir African American Photograph Collection, n.d. Box 72. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/552w3r22bf-cor.