MLA

H. D. (Hilda Doolittle), 1886-1961. Aldington, Richard. Box 1, folder 5-35. 1918-56. https://collections.library.yale.edu/catalog/16083714.

APA, 6th edition

H. D. (Hilda Doolittle), 1886-1961. (["Box 1, folder 5-35"])(1918-56)[Aldington, Richard]. https://collections.library.yale.edu/catalog/16083714.