Amazon.com Inc has halted pre-orders of some Disney movies, the Wall Street Journal reported, in what appears to be another contract dispute after the online retailer began a protracted spat with publisher Hachette Book Group this year. Amazon has been waging a battle against Hachette, the fourth-largest U.S. book publisher, over the price the online retailer can charge for e-books. A group called Authors United ran a two-page ad in the New York Times on Sunday, criticizing Amazon for halting pre-orders from some Hachette authors and slowing delivery of books by Hachette authors. The ad was signed by more than 900 writers, including Stephen King and Donna Tartt.