MLA
Anderson, J. W. Letter from J. W. Anderson to G. H.Thompson - August 3, 1889 (Photocopy). 1889. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 3, Folder 49. https://digital.library.emory.edu/purl/972p5hqd0n-cor.
APA, 6th edition
Anderson, J. W. (1889). Letter from J. W. Anderson to G. H.Thompson - August 3, 1889 (photocopy) (Box 3, Folder 49) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/972p5hqd0n-cor.
Chicago
Anderson, J. W. “Letter from J. W. Anderson to G. H.Thompson - August 3, 1889 (Photocopy).” Letters (correspondence). Civil War Collection, 1889. Box 3, Folder 49. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/972p5hqd0n-cor.