MLA
Letter by Unknown Author to Lieutenant-Colonel [Illegible] (Photocopy). Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 3, Folder 49. https://digital.library.emory.edu/purl/559q2bvr8h-cor.
APA, 6th edition
Letter by unknown author to lieutenant-colonel [illegible] (photocopy) (Box 3, Folder 49). [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/559q2bvr8h-cor.
Chicago
“Letter by Unknown Author to Lieutenant-Colonel [Illegible] (Photocopy).” Letters (correspondence). Civil War Collection, n.d. Box 3, Folder 49. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/559q2bvr8h-cor.