MLA
Plummer, David R. Letters from Davis R. Plummer to His Wife and Family. Plummer Was a Private in the 32nd Maine Infantry Regiment. Plummer Wrote These Letters during the Siege of Petersburg and Contain Information about the Campaign. The Last Two Letters Are Written to His Wife and Contain Information about His Death by Typhoid Fever and His Burial in Alexandria, Virginia - May 14 to August 14, 1864 (Photocopy). 1864. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 20, Folder 12. https://digital.library.emory.edu/purl/064tht77nd-cor.
APA, 6th edition
Plummer, D. R. (1864). Letters from Davis R. Plummer to his wife and family. Plummer was a private in the 32nd Maine Infantry Regiment. Plummer wrote these letters during the Siege of Petersburg and contain information about the campaign. The last two letters are written to his wife and contain information about his death by typhoid fever and his burial in Alexandria, Virginia - May 14 to August 14, 1864 (photocopy) (Box 20, Folder 12) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/064tht77nd-cor.
Chicago
Plummer, David R. “Letters from Davis R. Plummer to His Wife and Family. Plummer Was a Private in the 32nd Maine Infantry Regiment. Plummer Wrote These Letters during the Siege of Petersburg and Contain Information about the Campaign. The Last Two Letters Are Written to His Wife and Contain Information about His Death by Typhoid Fever and His Burial in Alexandria, Virginia - May 14 to August 14, 1864 (Photocopy).” Letters (correspondence). Civil War Collection, 1864. Box 20, Folder 12. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/064tht77nd-cor.