Barnes & Noble to spin off Nook e-readers

US bookstore Barnes & Noble will split into two companies by the first quarter of next year. The retail stores will separate from Nook Media, which sells an e-reader device, the Nook, along with e-books. Barnes & Noble’s Nook device has struggled to compete in the e-reader tablet market. Last quarter, Nook posted a 22 per cent revenue decline to $87m.