The Exorcist is written by William Peter Blatty
[Human]: Do you know who is the author of The Exorcist? I have no idea about this book [Assistant]: Yes, The Exorcist is written by William Peter Blatty and stars Linda Blair. It's considered a horror, do you like horrors? [Human]: Oh I love horror movies, but not read any book , can you recommend any horror book [Assistant]: Would you like horrors by Peter Blatty if available or horror books in general? [Human]: Yeah sure any horror books  
OK, perhaps you would like Edgar Allan Poe's The Raven or The Tell-Tale Heart. Both are excellent horror books.