There are interviews with authors and scholarly lectures available on YouTube about different manga, graphic novels, and comics, as well as general discussions. So, don't forget to check those out!
Search a selection of print and electronic encyclopedias, dictionaries, and other Reference books.
Comics, Comix, Graphic Novels, manga, manhwa, manhua, etc. are often differentiated from one another based on style though the format or content can be similar. When doing research you might want to try these different words in your search.