MLA
Young, Bennett H. Letter to William Berrien Burroughs from Bennett H. Young, on United Confederate Veteran Association Stationery, Promising to Send Him a Copy of His Book, "Confederate Wizards of the Saddle" - November 11, 1914. 1914. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 1, Folder 46. https://digital.library.emory.edu/purl/11615dv543-cor.
APA, 6th edition
Young, B. H. (1914). Letter to William Berrien Burroughs from Bennett H. Young, on United Confederate Veteran Association stationery, promising to send him a copy of his book, "Confederate Wizards of the Saddle" - November 11, 1914 (Box 1, Folder 46) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/11615dv543-cor.
Chicago
Young, Bennett H. “Letter to William Berrien Burroughs from Bennett H. Young, on United Confederate Veteran Association Stationery, Promising to Send Him a Copy of His Book, ‘Confederate Wizards of the Saddle’ - November 11, 1914.” Letters (correspondence). Civil War Collection, 1914. Box 1, Folder 46. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/11615dv543-cor.