After looking at hundreds of comic book covers, it becomes quickly apparent that not every cover is 100% original. Whether done intentionally or even underhandedly, there's something about uncovering these "swipes" that adds a new element of fun to reading and collecting comics. Simpsons Comics #4 utilized an "infinity cover" design by Matt Groening. Nine years later, they swiped their own cover!
the Simpsons #4 Simpsons Comics #4
May 1994
Matt Groening
 the Simpsons #85 Simpsons Comics #85
August 2003
Matt Groening
On Ebay: Simpsons On AtomicAvenue: Simpsons