MLA
Walker, John K. Letter from John K. Walker (Camp Winchester in Virginia) to His Father and Mother. Walker Served in Company K of the 6th North Carolina Regiment - June 11, 1865. 1865. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 7, Folder 8. https://digital.library.emory.edu/purl/921ghx3gfv-cor.
APA, 6th edition
Walker, J. K. (1865). Letter from John K. Walker (Camp Winchester in Virginia) to his father and mother. Walker served in Company K of the 6th North Carolina Regiment - June 11, 1865 (Box 7, Folder 8) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/921ghx3gfv-cor.
Chicago
Walker, John K. “Letter from John K. Walker (Camp Winchester in Virginia) to His Father and Mother. Walker Served in Company K of the 6th North Carolina Regiment - June 11, 1865.” Letters (correspondence). Civil War Collection, 1865. Box 7, Folder 8. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/921ghx3gfv-cor.