MLA
Ryan, D. J. Robert E. Lee and Joseph E. Johnston in 1870. 1870. Stuart A. Rose Manuscript, Archives, and Rare Book Library, OP6, Folder 11. https://digital.library.emory.edu/purl/477sn02wbv-cor.
APA, 6th edition
Ryan, D. J. (1870). Robert E. Lee and Joseph E. Johnston in 1870 (OP6, Folder 11) [Black-and-white photographs]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/477sn02wbv-cor.
Chicago
Ryan, D. J. “Robert E. Lee and Joseph E. Johnston in 1870.” Black-and-white photographs. Civil War Collection. Savannah, GA, 1870. OP6, Folder 11. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/477sn02wbv-cor.