In Defense of Dots: The lost art of comic books -

"From the 1940s to the 1970s, comic book art and comic books were the same thing. In the decades since, the art of comics has been carefully separated from the original physical conditions of its reproduction. Elevation of the 20th century art form has resulted in the erasure of the 20th century mechanical processes that enabled comic books to exist and thrive – for ten, twelve, fifteen, or twenty cents, millions of times over."
In Defense of Dots: The lost art of comic books, 4CP Four Color Process