MLA
Hartsfield, William Berry. Letter from William B. Hartsfield, Mayor of Atlanta, to Reverend Otis Moss Jr. Regarding Boycotts Related to Segregation - November 2, 1960. 1960. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 37, Folder 3. https://digital.library.emory.edu/purl/6042rbp07x-cor.
APA, 6th edition
Hartsfield, W. B. (1960). Letter from William B. Hartsfield, Mayor of Atlanta, to Reverend Otis Moss Jr. regarding boycotts related to segregation - November 2, 1960 (Box 37, Folder 3) [Correspondence]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/6042rbp07x-cor.
Chicago
Hartsfield, William Berry. “Letter from William B. Hartsfield, Mayor of Atlanta, to Reverend Otis Moss Jr. Regarding Boycotts Related to Segregation - November 2, 1960.” Correspondence. Richard H. Rich Papers, 1902-1981, 1960. Box 37, Folder 3. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/6042rbp07x-cor.