MLA

Trudeau, G. B., 1948-. Daily pencils. Box 161. [2001?]. https://collections.library.yale.edu/catalog/2053567.

APA, 6th edition

Trudeau, G. B., 1948-. (["Box 161"])([2001?])[Daily pencils]. https://collections.library.yale.edu/catalog/2053567.