MLA

Seymour, George Dudley, 1859-1945. Political cartoons. Box 81, folder 1200. undated. https://collections.library.yale.edu/catalog/10012298.

APA, 6th edition

Seymour, George Dudley, 1859-1945. (["Box 81, folder 1200"])(undated)[Political cartoons]. https://collections.library.yale.edu/catalog/10012298.