MLA
Bullock, Rufus B. (Rufus Brown), 1834-1907. Letter from Georgia governor Rufus Brown Bullock (Atlanta, Georgia) to Ben W. Austin - November 15, 1886. November 15, 1886. Civil War Collection. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/972p5hqd3z-cor.
APA, 6th edition
Bullock, Rufus B. (Rufus Brown), 1834-1907. (November 15, 1886)[Letter from Georgia governor Rufus Brown Bullock (Atlanta, Georgia) to Ben W. Austin - November 15, 1886]. Civil War Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/972p5hqd3z-cor.
Chicago
Bullock, Rufus B. (Rufus Brown), 1834-1907, Letter from Georgia governor Rufus Brown Bullock (Atlanta, Georgia) to Ben W. Austin - November 15, 1886, November 15, 1886, Civil War Collection, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/972p5hqd3z-cor.