MLA

H. D. (Hilda Doolittle), 1886-1961. Freud, Sigmund. Box 53, folder 1330. n.d.. https://collections.library.yale.edu/catalog/2057135.

APA, 6th edition

H. D. (Hilda Doolittle), 1886-1961. (["Box 53, folder 1330"])(n.d.)[Freud, Sigmund]. https://collections.library.yale.edu/catalog/2057135.