MLA

Wharton, Edith, 1862-1937. Tyler, Elisina Royall. Box 54, folder 1615. c. 1910. https://collections.library.yale.edu/catalog/2042333.

APA, 6th edition

Wharton, Edith, 1862-1937. (["Box 54, folder 1615"])(c. 1910)[Tyler, Elisina Royall]. https://collections.library.yale.edu/catalog/2042333.