MLA
Spencer, Thomas. Location Where Sam Davis, "Boy Hero of the Confederacy", Was Executed in Pulaski, Tennessee. 1940. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 15, Folder 7. https://digital.library.emory.edu/purl/774qjq2d07-cor.
APA, 6th edition
Spencer, T. (1940). Location where Sam Davis, "Boy Hero of the Confederacy", was executed in Pulaski, Tennessee (Box 15, Folder 7) [Black-and-white photographs]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/774qjq2d07-cor.
Chicago
Spencer, Thomas. “Location Where Sam Davis, ‘Boy Hero of the Confederacy’, Was Executed in Pulaski, Tennessee.” Black-and-white photographs. Civil War Collection, 1940. Box 15, Folder 7. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/774qjq2d07-cor.