MLA

Wilson, Edmund, 1895-1972. Canby, Margaret. Box 15, folder 343-347. 1929-32, n.d.. https://collections.library.yale.edu/catalog/17083221.

APA, 6th edition

Wilson, Edmund, 1895-1972. (["Box 15, folder 343-347"])(1929-32, n.d.)[Canby, Margaret]. https://collections.library.yale.edu/catalog/17083221.