Copyrights, copyrights

So for the most part I've tried to stay away from doing book illustrations for clients, simply because I have NO idea what I should charge for royalties/copyrights, or even if that's possible. I was just approached to do a book cover, and while doing a bit of internet research, found this article that helped me explain how copyrights are formed and why contracts are so important. A good read, if you've ever wondered about how it works!