Wikisimpsons - The Simpsons Wiki
 References to the show
A spoof of South Park appeared in the episode "The Bart of War" as a response from the showrunners after South Park parodied their show in the episode "Simpsons Already Did It".
In "Oh Brother, Where Bart Thou?", there is a scene referencing South Park involving Bart, Milhouse, Nelson and Ralph waiting at a bus stop, dressing up exactly like characters Stan Marsh, Kyle Broflovski, Eric Cartman, and Kenny McCormick, respectively. Ralph gets hit by a school bus driven by Otto, who remarks "Oh my god, I killed Kenny!".
 See also