Cite

Pin, "For progress in writing"

MLA

Wilson, Edmund, 1895-1972. Pin, "For progress in writing". Box 205, folder 5039. n.d.. https://collections.library.yale.edu/catalog/2005099.

APA, 6th edition

Wilson, Edmund, 1895-1972. (["Box 205, folder 5039"])(n.d.)[Pin, "For progress in writing"]. https://collections.library.yale.edu/catalog/2005099.