Here's a small sampling of Williamson's work. The sumptuous artwork speaks for itself.
I only recently discovered Williamson's work from the Flash Gordon film released in 1980. It's absolutely beautiful. Unlike the campy tone of the movie, the comic book adaptation played it straight. I highly recommend the book Al Williamson's Flash Gordon: A Lifelong Vision of the Heroic, edited by Mark Schultz, which gorgeously reprints the Flash Gordon adaptation in its entirety.