MLA

Herbst, Josephine, 1892-1969. Dos Passos, John. Box 5. 1929-1949, undated. https://collections.library.yale.edu/catalog/10599427.

APA, 6th edition

Herbst, Josephine, 1892-1969. (["Box 5"])(1929-1949, undated)[Dos Passos, John]. https://collections.library.yale.edu/catalog/10599427.