MLA
Braun. Portrait of Peter Williams, an Ex-Slave Clergyman. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 74. https://digital.library.emory.edu/purl/914nk98sj2-cor.
APA, 6th edition
B. Portrait of Peter Williams, an ex-slave clergyman (Box 74) [Postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/914nk98sj2-cor.
Chicago
Braun. “Portrait of Peter Williams, an Ex-Slave Clergyman.” Postcards. Robert Langmuir African American Photograph Collection, n.d. Box 74. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/914nk98sj2-cor.