MLA
Baltimore Stationery Co. (Baltimore, Md.). John Brown's Fort, Harpers Ferry, W. Va. : and a portrait of John Brown. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/081wdbrv4j-cor.
APA, 6th edition
Baltimore Stationery Co. (Baltimore, Md.). (unknown)[John Brown's Fort, Harpers Ferry, W. Va. : and a portrait of John Brown]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/081wdbrv4j-cor.
Chicago
Baltimore Stationery Co. (Baltimore, Md.), John Brown's Fort, Harpers Ferry, W. Va. : and a portrait of John Brown, unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/081wdbrv4j-cor.