MLA
Gonne, Maud, 1866-1953. Letter written by Maud Gonne to William Butler Yeats - [ca. August or September 1902]. between 1902-08 and 1902-09. 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/856n02v93q-cor.
APA, 6th edition
Gonne, Maud, 1866-1953. (between 1902-08 and 1902-09)[Letter written by Maud Gonne to William Butler Yeats - [ca. August or September 1902]]. 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/856n02v93q-cor.
Chicago
Gonne, Maud, 1866-1953, Letter written by Maud Gonne to William Butler Yeats - [ca. August or September 1902], between 1902-08 and 1902-09, 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/856n02v93q-cor.