Random House has so far refused to sign up for Apple's iBookstore because it might trigger a fight over e-book pricing, the publisher's CEO Markus Dohle said Tuesday. The executive hinted that a deal with Apple was still an option even with just days left before the iPad's launch but that Apple's insistence on taking a 30 percent cut would force Random House to give up pricing control. He preferred a wholesale model used by Amazon and some physical stores, where retailers buy the books at a set price and then charge extra to meet their needs.