First Doonesbury by Garry Trudeau for October 26, 1970
Transcript:
B.D. Well, here I sit at college awaiting my new roommate. I know he'll be cool, since he's computer selected!! You just fill in a form, send it in, and presto! Ideal roommates! Mike: Hi there! My name's Mike Doonesbury. I hail from Tulsa, Oklahoma and women adore me! Glad to meet you, roomie! B.D.: Of course, there are still a few bugs in the system.
the first published strip included 3-way parallelism as the set-up