MLA
Scott, William H. (William Henry), 1887-1976. Letter from William H. Scott, Jr. to his father, William H. Scott, Sr., May 18, 1897. May 18, 1897. William H. Scott Family Papers, 1848-1982. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/27312jm7kv-cor.
APA, 6th edition
Scott, William H. (William Henry), 1887-1976. (May 18, 1897)[Letter from William H. Scott, Jr. to his father, William H. Scott, Sr., May 18, 1897]. William H. Scott Family Papers, 1848-1982, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/27312jm7kv-cor.
Chicago
Scott, William H. (William Henry), 1887-1976, Letter from William H. Scott, Jr. to his father, William H. Scott, Sr., May 18, 1897, May 18, 1897, William H. Scott Family Papers, 1848-1982, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/27312jm7kv-cor.