MLA
Teich, Curt, and Co. Old Slave Mart Museum, Charleston, South Carolina. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 74. https://digital.library.emory.edu/purl/211kh18954-cor.
APA, 6th edition
Teich, C., & C. Old Slave Mart Museum, Charleston, South Carolina (Box 74) [Postcards]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/211kh18954-cor.
Chicago
Teich, Curt, and Co. “Old Slave Mart Museum, Charleston, South Carolina.” 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/211kh18954-cor.