Doonesbury by Garry Trudeau for April 18, 1980
Transcript:
Mark: It's a good way to help, campers, so if you dig Duke the way I do, get on down to your bookstore and pick up "Duke: Portrait of a Mentor!" Remember, for every copy sold, Zeke Brenner will be donating a share of his royalties to fund an urgent investigation into Duke's fate! Hello. Marvelous Mark show! How big a share? Zeke: Maybe 2%. There's not much hope.