MLA
Price, Milton. Harvesting Long Island Potatoes. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 69. https://digital.library.emory.edu/purl/4407wm37t7-cor.
APA, 6th edition
Price, M. Harvesting Long Island potatoes (Box 69) [Photographic postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4407wm37t7-cor.
Chicago
Price, Milton. “Harvesting Long Island Potatoes.” Photographic postcards. Robert Langmuir African American Photograph Collection, n.d. Box 69. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4407wm37t7-cor.