MLA

Broch, Hermann, 1886-1951. "J" general. Box 20, folder 631. 1943. https://collections.library.yale.edu/catalog/17268014.

APA, 6th edition

Broch, Hermann, 1886-1951. (["Box 20, folder 631"])(1943)["J" general]. https://collections.library.yale.edu/catalog/17268014.