GET THEE TO A LIBRARY
Do yourself a favour and sit down at the Online Public Access Catalogue in your local library and do a search on "comics" and "graphic novels". I've tried this in a few different authorities and it always yields results.
Today I got hold of What children think of their comics by George H. Pumphrey, published in 1964. It's a snapshot of an attitude from another time. I know I am going to enjoy reading it, as flicking through it I read this snippet:
"Superman and Superboy fulfill the wildest phantasies, and to the mature adult seem stupid and humourless in their fantastic adventures. Adult violence and undesirable criminal activities still flourish in these American-type magazines and one can only deplore their existence. The Poole Education Committee in August 1963 urged a ban on the importation of this kind of magazine, and they will have the support of all adults who examine these publications."