Workers at Great Northern Paper Company in East Millinocket plan to turn out another 750 tons of paper this week for one of the fastest selling book series of all times. The demand for the books in the Fifty Shades trilogy has turned into to big business for the mill. So far, they’ve made more than 3,000 tons of Baxter Brite Grade paper for the books. The paper’s shipped to printers around the country.The book series has sold more than 10 million copies in the United States and workers at GNP say they’re proud to be a part of that success.David Jamo, an engineer, says, ‘It’s a great thing. Whether it was Fifty Shades of Grey or a cookbook, we’re making paper for it and it’s off the presses and selling like made and we’re happy to make it.”The three novels in the Fifty Shades series claim the top three spots on the New York Times Best Sellers list for paperback fiction.