MLA
Rogers, J. C. Donation of Rees P. Smart's Letter to Emory University by Distant Relative, T. C. Rogers. 1959. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 6, Folder 26. https://digital.library.emory.edu/purl/805fbg7b30-cor.
APA, 6th edition
Rogers, J. C. (1959). Donation of Rees P. Smart's letter to Emory University by distant relative, T. C. Rogers (Box 6, Folder 26) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/805fbg7b30-cor.
Chicago
Rogers, J. C. “Donation of Rees P. Smart's Letter to Emory University by Distant Relative, T. C. Rogers.” Letters (correspondence). Civil War Collection, 1959. Box 6, Folder 26. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/805fbg7b30-cor.