MLA
Dittmeyer, W. E. Men Standing in Front of John Brown's Fort, in Harpers Ferry, West Virginia. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 69. https://digital.library.emory.edu/purl/358bg79crh-cor.
APA, 6th edition
Dittmeyer, W. E. Men standing in front of John Brown's Fort, in Harpers Ferry, West Virginia (Box 69) [Postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/358bg79crh-cor.
Chicago
Dittmeyer, W. E. “Men Standing in Front of John Brown's Fort, in Harpers Ferry, West Virginia.” 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/358bg79crh-cor.