MLA

Trudeau, G. B., 1948-. Doonesbury. Box 1978. 1978 July 28. https://collections.library.yale.edu/catalog/2052821.

APA, 6th edition

Trudeau, G. B., 1948-. (["Box 1978"])(1978 July 28)[Doonesbury]. https://collections.library.yale.edu/catalog/2052821.