MLA

Wharton, Edith, 1862-1937. Pulitzer Prize certificate. folder 1838 (broadside). 1921. https://collections.library.yale.edu/catalog/2014297.

APA, 6th edition

Wharton, Edith, 1862-1937. (["folder 1838 (broadside)"])(1921)[Pulitzer Prize certificate]. https://collections.library.yale.edu/catalog/2014297.