MLA

McKay, Claude, 1890-1948. Nussbaum, Anna. Box 5, folder 162. 1928. https://collections.library.yale.edu/catalog/16742356.

APA, 6th edition

McKay, Claude, 1890-1948. (["Box 5, folder 162"])(1928)[Nussbaum, Anna]. https://collections.library.yale.edu/catalog/16742356.