MLA

Luhan, Mabel Dodge, 1879-1962. James, Edward. Box 19, folder 537. 1940-41, n.d.. https://collections.library.yale.edu/catalog/32196375.

APA, 6th edition

Luhan, Mabel Dodge, 1879-1962. (["Box 19, folder 537"])(1940-41, n.d.)[James, Edward]. https://collections.library.yale.edu/catalog/32196375.