MLA
Gonne, Maud, 1866-1953. Letter written by Maud Gonne to William Butler Yeats - January 8 [1908]. January 1908. Maud Gonne and W.B. Yeats Papers, circa 1890-1938. Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/40644j11rk-cor.
APA, 6th edition
Gonne, Maud, 1866-1953. (January 1908)[Letter written by Maud Gonne to William Butler Yeats - January 8 [1908]]. Maud Gonne and W.B. Yeats Papers, circa 1890-1938, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/40644j11rk-cor.
Chicago
Gonne, Maud, 1866-1953, Letter written by Maud Gonne to William Butler Yeats - January 8 [1908], January 1908, Maud Gonne and W.B. Yeats Papers, circa 1890-1938, Stuart A. Rose Manuscript, Archives, and Rare Book Library. https://digital.library.emory.edu/purl/40644j11rk-cor.