MLA
Thomas, Robert. Way down South in Dixie : an African American Family Outside a House, with Two Horses and a Cart. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 71. https://digital.library.emory.edu/purl/7032280gcx-cor.
APA, 6th edition
Thomas, R. Way down south in Dixie : an African American family outside a house, with two horses and a cart (Box 71) [Photographic postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/7032280gcx-cor.
Chicago
Thomas, Robert. “Way down South in Dixie : an African American Family Outside a House, with Two Horses and a Cart.” Photographic postcards. Robert Langmuir African American Photograph Collection, n.d. Box 71. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/7032280gcx-cor.