MLA
Letter from Unidentified Person to James Scarth Gale - January 12, 1918. 1918. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 17, Folder 3. https://digital.library.emory.edu/purl/511xd255fj-cor.
APA, 6th edition
Letter from unidentified person to James Scarth Gale - January 12, 1918 (Box 17, Folder 3). (1918). [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/511xd255fj-cor.
Chicago
“Letter from Unidentified Person to James Scarth Gale - January 12, 1918.” Letters (correspondence). Yun Ch‘i-Ho Papers, 1918. Box 17, Folder 3. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/511xd255fj-cor.