MLA
Powell, J. C. Phosphate Mining, Fort Meade, Fla. 1916. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 71. https://digital.library.emory.edu/purl/668x95x6g7-cor.
APA, 6th edition
Powell, J. C. (1916). Phosphate mining, Fort Meade, Fla. (Box 71) [Photographic postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/668x95x6g7-cor.
Chicago
Powell, J. C. “Phosphate Mining, Fort Meade, Fla.” Photographic postcards. Robert Langmuir African American Photograph Collection, 1916. Box 71. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/668x95x6g7-cor.