MLA
Manley, John Washington Jeremiah. Letter from Joseph W. Manley to His Family (Franklin County, Georgia). Manley Served in Company H of the 34th Georgia Infantry Regiment - May 19, 1863. 1863. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 4, Folder 57. https://digital.library.emory.edu/purl/11615dv54x-cor.
APA, 6th edition
Manley, J. W. J. (1863). Letter from Joseph W. Manley to his family (Franklin County, Georgia). Manley served in Company H of the 34th Georgia Infantry Regiment - May 19, 1863 (Box 4, Folder 57) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/11615dv54x-cor.
Chicago
Manley, John Washington Jeremiah. “Letter from Joseph W. Manley to His Family (Franklin County, Georgia). Manley Served in Company H of the 34th Georgia Infantry Regiment - May 19, 1863.” Letters (correspondence). Civil War Collection, 1863. Box 4, Folder 57. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/11615dv54x-cor.