MLA
Letters Written by Unidentified Union Soldiers or Civilians during the Civil War. 1862. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 20, Folder 34. https://digital.library.emory.edu/purl/136h189461-cor.
APA, 6th edition
Letters written by unidentified Union soldiers or civilians during the Civil War (Box 20, Folder 34). (1862). [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/136h189461-cor.
Chicago
“Letters Written by Unidentified Union Soldiers or Civilians during the Civil War.” Letters (correspondence). Civil War Collection, 1862. Box 20, Folder 34. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/136h189461-cor.