MLA

Hartley, Marsden, 1877-1943. Marc, Franz. Box 14. 1913. https://collections.library.yale.edu/catalog/11194865.

APA, 6th edition

Hartley, Marsden, 1877-1943. (["Box 14"])(1913)[Marc, Franz]. https://collections.library.yale.edu/catalog/11194865.