MLA
Letter from an Unknown Soldier (Richmond, Virginia) to "Dear Brother". The Unknown Soldier Probably Served in the Company E of the 12th Alabama Infantry Regiment (DeKalb Invincibles) - August 17, 1862. 1862. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 6, Folder 76. https://digital.library.emory.edu/purl/235gb5mm9f-cor.
APA, 6th edition
Letter from an unknown soldier (Richmond, Virginia) to "Dear Brother". The unknown soldier probably served in the Company E of the 12th Alabama Infantry Regiment (DeKalb Invincibles) - August 17, 1862 (Box 6, Folder 76). (1862). [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/235gb5mm9f-cor.
Chicago
“Letter from an Unknown Soldier (Richmond, Virginia) to ‘Dear Brother’. The Unknown Soldier Probably Served in the Company E of the 12th Alabama Infantry Regiment (DeKalb Invincibles) - August 17, 1862.” Letters (correspondence). Civil War Collection, 1862. Box 6, Folder 76. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/235gb5mm9f-cor.