MLA

Butts, Mary, 1890-1937. "On Vexin," typescript. Box 6, folder 105. n.d.. https://collections.library.yale.edu/catalog/16586547.

APA, 6th edition

Butts, Mary, 1890-1937. (["Box 6, folder 105"])(n.d.)["On Vexin," typescript]. https://collections.library.yale.edu/catalog/16586547.