MLA
Young, Bennett H. Letter from Bennet H. Young (Louisville, Kentucky) to General William E. Mickle, Regarding Contracts Relating to the Southeastern Passenger Association. Bennett H. Young Was a Member of the United Confederate Veterans Organization - February 1, 1905. 1905. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 9, Folder 51. https://digital.library.emory.edu/purl/12683bk4kr-cor.
APA, 6th edition
Young, B. H. (1905). Letter from Bennet H. Young (Louisville, Kentucky) to General William E. Mickle, regarding contracts relating to the Southeastern Passenger Association. Bennett H. Young was a member of the United Confederate Veterans organization - February 1, 1905 (Box 9, Folder 51) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/12683bk4kr-cor.
Chicago
Young, Bennett H. “Letter from Bennet H. Young (Louisville, Kentucky) to General William E. Mickle, Regarding Contracts Relating to the Southeastern Passenger Association. Bennett H. Young Was a Member of the United Confederate Veterans Organization - February 1, 1905.” Letters (correspondence). Civil War Collection, 1905. Box 9, Folder 51. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/12683bk4kr-cor.