MLA
Eddy, E. C. Two Coons and One Posum : an African American Man with a Fox and and an Opossum, with a Dog on the Side in So. Pines, N.C. 1917. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 69. https://digital.library.emory.edu/purl/8021c5b00j-cor.
APA, 6th edition
Eddy, E. C. (1917). Two coons and one posum : an African American man with a fox and and an opossum, with a dog on the side in So. Pines, N.C. (Box 69) [Postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/8021c5b00j-cor.
Chicago
Eddy, E. C. “Two Coons and One Posum : an African American Man with a Fox and and an Opossum, with a Dog on the Side in So. Pines, N.C.” Postcards. Robert Langmuir African American Photograph Collection, 1917. Box 69. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/8021c5b00j-cor.