MLA
Edmonds, George W. Letter from George W. Edmonds to His Sister. During the Civil War Edmonds Served in the 1st Arkansas Infantry Regiment; after the War He Joined the United State Army and Was Stationed at Fort Halleck, Dakota Territory (Wyoming) - May 27, 1866. 1866. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 3, Folder 16. https://digital.library.emory.edu/purl/351hhmgrpx-cor.
APA, 6th edition
Edmonds, G. W. (1866). Letter from George W. Edmonds to his sister. During the Civil War Edmonds served in the 1st Arkansas Infantry Regiment; after the war he joined the United State Army and was stationed at Fort Halleck, Dakota Territory (Wyoming) - May 27, 1866 (Box 3, Folder 16) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/351hhmgrpx-cor.
Chicago
Edmonds, George W. “Letter from George W. Edmonds to His Sister. During the Civil War Edmonds Served in the 1st Arkansas Infantry Regiment; after the War He Joined the United State Army and Was Stationed at Fort Halleck, Dakota Territory (Wyoming) - May 27, 1866.” Letters (correspondence). Civil War Collection, 1866. Box 3, Folder 16. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/351hhmgrpx-cor.