MLA
Anderson, Jim L. Letter from David L. Anderson (Wynn's Mill, Virginia) to His Father, Saxon Anderson (Talladega, Alabama). David L. Anderson Served in the 8th Alabama Infantry Regiment - April 3, 1862. 1862. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 1, Folder 4. https://digital.library.emory.edu/purl/856n02v7zp-cor.
APA, 6th edition
Anderson, J. L. (1862). Letter from David L. Anderson (Wynn's Mill, Virginia) to his father, Saxon Anderson (Talladega, Alabama). David L. Anderson served in the 8th Alabama Infantry Regiment - April 3, 1862 (Box 1, Folder 4) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/856n02v7zp-cor.
Chicago
Anderson, Jim L. “Letter from David L. Anderson (Wynn's Mill, Virginia) to His Father, Saxon Anderson (Talladega, Alabama). David L. Anderson Served in the 8th Alabama Infantry Regiment - April 3, 1862.” Letters (correspondence). Civil War Collection, 1862. Box 1, Folder 4. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/856n02v7zp-cor.