The comic strips referenced in this episode include Peanuts, Blondie, Dick Tracy, various Marvel Comics characters (and a cameo by Stan Lee who created many of them), Popeye, Mary Worth, Little Orphan Annie, Prince Valiant, Apartment 3-G, Crock, and Hagar the Horrible.
Source:IMDB
Lee appeared in the 1989 Muppet Babies episode “Comic Capers.” After Baby Rowlf and Skeeter enter the Spider-Man newspaper strip, Lee appears, hovering over a drawing desk, and takes the kids to task: “Don’t you know there’s only one Spider-Man?” Rowlf is apologetic (“Sorry, Mr. Lee”), but Skeeter accidentally releases a stream of webbing at Stan, coating his head with it.
Source:Muppet Wiki