Simpsons, The Easter Egg - Mental Patients

In The Simpsons episode Hurricane Neddy (the episode the Flanders' house gets destroyed by a hurricane and Ned goes crazy), when the Simpsons visit the mental hospital, the doctor says to them one of his three patients is a cannibal. The first patient is Jay Sherman, the main character in Matt Groenings show The Critic. The next patient is the babysitter robber and the third is John Swartzwelder, a writer on the Simpsons