MLA
Evans, Clement A. Letter from Clement A. Evans (Atlanta, Georgia) to the Adjutant of Raphael Semmes Camp (Mobile, Alabama) Regarding the Publication of a Multi-Volume Confederate Military History Series and Asking for Assistance in the Editorial Work to Come - January 6, 1900. 1900. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 8, Folder 23. https://digital.library.emory.edu/purl/436tx95xwn-cor.
APA, 6th edition
Evans, C. A. (1900). Letter from Clement A. Evans (Atlanta, Georgia) to the Adjutant of Raphael Semmes camp (Mobile, Alabama) regarding the publication of a multi-volume Confederate Military History series and asking for assistance in the editorial work to come - January 6, 1900 (Box 8, Folder 23) [Correspondence]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/436tx95xwn-cor.
Chicago
Evans, Clement A. “Letter from Clement A. Evans (Atlanta, Georgia) to the Adjutant of Raphael Semmes Camp (Mobile, Alabama) Regarding the Publication of a Multi-Volume Confederate Military History Series and Asking for Assistance in the Editorial Work to Come - January 6, 1900.” Correspondence. Civil War Collection, 1900. Box 8, Folder 23. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/436tx95xwn-cor.