MLA
Carroll, Jeremiah. Letter from Jeremiah Carroll to Mr. Shuler. Jeremiah Carroll, Served in Company F of the 6th South Carolina Infantry Regiment. 1861. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 6, Folder 21. https://digital.library.emory.edu/purl/1741rn8q8m-cor.
APA, 6th edition
Carroll, J. (1861). Letter from Jeremiah Carroll to Mr. Shuler. Jeremiah Carroll, served in Company F of the 6th South Carolina Infantry Regiment (Box 6, Folder 21) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/1741rn8q8m-cor.
Chicago
Carroll, Jeremiah. “Letter from Jeremiah Carroll to Mr. Shuler. Jeremiah Carroll, Served in Company F of the 6th South Carolina Infantry Regiment.” Letters (correspondence). Civil War Collection, 1861. Box 6, Folder 21. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/1741rn8q8m-cor.