MLA

Trudeau, G. B., 1948-. Doonesbury. Box 1986. 1986 October 21. https://collections.library.yale.edu/catalog/2053138.

APA, 6th edition

Trudeau, G. B., 1948-. (["Box 1986"])(1986 October 21)[Doonesbury]. https://collections.library.yale.edu/catalog/2053138.