MLA
Silvis, Doug. Letter from Doug Silvis, President of SGA [Student Government Association], to Dean Charles Beall, Regarding an Anti-War Rally on April 17, 1970 - April 30, 1970. 1970. Stuart A. Rose Manuscript, Archives, and Rare Book Library, Box 6, Folder 2. https://digital.library.emory.edu/purl/914nk98tr4-cor.
APA, 6th edition
Silvis, D. (1970). Letter from Doug Silvis, President of SGA [Student Government Association], to Dean Charles Beall, regarding an anti-war rally on April 17, 1970 - April 30, 1970 (Box 6, Folder 2) [Letters (correspondence)]. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/914nk98tr4-cor.
Chicago
Silvis, Doug. “Letter from Doug Silvis, President of SGA [Student Government Association], to Dean Charles Beall, Regarding an Anti-War Rally on April 17, 1970 - April 30, 1970.” Letters (correspondence). Student Government Association Records, 1970. Box 6, Folder 2. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/914nk98tr4-cor.