MLA

H. D. (Hilda Doolittle), 1886-1961. Gaudier-Brzeska, Henri. Box 50, folder 1269. 1960. https://collections.library.yale.edu/catalog/17064299.

APA, 6th edition

H. D. (Hilda Doolittle), 1886-1961. (["Box 50, folder 1269"])(1960)[Gaudier-Brzeska, Henri]. https://collections.library.yale.edu/catalog/17064299.