MLA
Confederate General Joseph Eggleston Johnston. Copy of Photograph given to James Longstreet by Joseph Eggleston Johnston. 1861. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 16, Folder 40. https://digital.library.emory.edu/purl/4579s4mww1-cor.
APA, 6th edition
Confederate general Joseph Eggleston Johnston. Copy of photograph given to James Longstreet by Joseph Eggleston Johnston (Box 16, Folder 40). (1861). [Black-and-white photographs]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4579s4mww1-cor.
Chicago
“Confederate General Joseph Eggleston Johnston. Copy of Photograph given to James Longstreet by Joseph Eggleston Johnston.” Black-and-white photographs. Civil War Collection, 1861. Box 16, Folder 40. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/4579s4mww1-cor.