MLA

Matthiessen, F. O. (Francis Otto), 1902-1950. Huberman, Leo. Box 2. 1949-1950. https://collections.library.yale.edu/catalog/32239708.

APA, 6th edition

Matthiessen, F. O. (Francis Otto), 1902-1950. (["Box 2"])(1949-1950)[Huberman, Leo]. https://collections.library.yale.edu/catalog/32239708.