MLA

Hartley, Marsden, 1877-1943. Other Material. Box 30. 1938-1943, undated. https://collections.library.yale.edu/catalog/16721059.

APA, 6th edition

Hartley, Marsden, 1877-1943. (["Box 30"])(1938-1943, undated)[Other Material]. https://collections.library.yale.edu/catalog/16721059.