MLA
Artvue Post Card Co. (New York, N.Y.). Charlie, porter at Seven Springs Hotel, Seven Springs, N.C.. unknown. Robert Langmuir African American Photograph Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/286nzs7h73-cor.
APA, 6th edition
Artvue Post Card Co. (New York, N.Y.). (unknown)[Charlie, porter at Seven Springs Hotel, Seven Springs, N.C.]. Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/286nzs7h73-cor.
Chicago
Artvue Post Card Co. (New York, N.Y.), Charlie, porter at Seven Springs Hotel, Seven Springs, N.C., unknown, Robert Langmuir African American Photograph Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/286nzs7h73-cor.