Difficult one to answer Vimto: there are plenty of Egyptology books that describe the discovery as a chapter or part of a chapter, but I don't know one I'd recommend that's just about this one discovery.
Maybe putting the enquiry into the wider context of the search to decipher hieroglyphic might return more options on a search - I just put that phrase into google / books and got a whole lot of sensible-looking book options. And there's always the side benefit of deciding to learn hiergogluphic oneself....