When an artist needed a visual reference, they relied on their “swipe files” … file folders cataloged and filled with images that were culled from any magazine they could get their hands on. Creating a swipe file is the learning method most professional comic book artists use to improve their work. Roy Lichstenstein famously pirated the art of Vince Colletta, Dick Giordano and others to create his signature pieces of pop art. I remember my father poring over the work of artist Hal Foster and his Prince Valiant books as an inspiration for how he wanted to ink THOR and Tales of Asgard. Artists study other people’s content and create a collection with proven examples. If you want to draw people with massive,bulging muscles, swipe from Jack Kirby or Frank Frazetta. If your goal is creating oddball art, Steve Ditko’s work qualifies. If your goal is learning how to illustrate beautiful women, look no further than the art of Vince Colletta.