MLA
Ward, A. J. Letter from A. J. Ward (Camp in Fredericksburg, Virginia) to His Father and Sisters - April 17, 1863. 1863. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 5, Folder 14. https://digital.library.emory.edu/purl/675r7sqwcc-cor.
APA, 6th edition
Ward, A. J. (1863). Letter from A. J. Ward (Camp in Fredericksburg, Virginia) to his father and sisters - April 17, 1863 (Box 5, Folder 14) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/675r7sqwcc-cor.
Chicago
Ward, A. J. “Letter from A. J. Ward (Camp in Fredericksburg, Virginia) to His Father and Sisters - April 17, 1863.” Letters (correspondence). Civil War Collection, 1863. Box 5, Folder 14. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/675r7sqwcc-cor.