MLA
Moffitt, A. J. Letter from A. J. Moffitt to Marey Moffitt. 1861. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 5, Folder 24. https://digital.library.emory.edu/purl/221tdz09n4-cor.
APA, 6th edition
Moffitt, A. J. (1861). Letter from A. J. Moffitt to Marey Moffitt (Box 5, Folder 24) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/221tdz09n4-cor.
Chicago
Moffitt, A. J. “Letter from A. J. Moffitt to Marey Moffitt.” Letters (correspondence). Civil War Collection, 1861. Box 5, Folder 24. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/221tdz09n4-cor.