MLA

Nichols, Dudley, 1895-1960. Toller, Ernst. Box 2. 1937 July 37. https://collections.library.yale.edu/catalog/17362260.

APA, 6th edition

Nichols, Dudley, 1895-1960. (["Box 2"])(1937 July 37)[Toller, Ernst]. https://collections.library.yale.edu/catalog/17362260.