MLA

Wilder, Thornton, 1897-1975. McDaniel, Walton Brooks. Box 48, folder 1268. 1973 Oct 8. https://collections.library.yale.edu/catalog/17056653.

APA, 6th edition

Wilder, Thornton, 1897-1975. (["Box 48, folder 1268"])(1973 Oct 8)[McDaniel, Walton Brooks]. https://collections.library.yale.edu/catalog/17056653.