MLA
Derker. Signed Picture of a Singing Trio. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 24. https://digital.library.emory.edu/purl/880ht76hk3-cor.
APA, 6th edition
D. Signed picture of a singing trio (Box 24) [Card photographs (photographs)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/880ht76hk3-cor.
Chicago
Derker. “Signed Picture of a Singing Trio.” Card photographs (photographs). Robert Langmuir African American Photograph Collection, n.d. Box 24. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/880ht76hk3-cor.