Since his first reading at the Udvar-Hazy bookstore in 2008 Robert F. Dorr has returned to sign books 330 more times!Over that time period the the bookstore has sold over 13,000 copies, half of all copies sold.What's the catch? Is Dorr aiming for the Guinness Book of World Records? No, Dorr has simply taken aim at his target audience. The book is Hell Hawks! The Untold Story of the American Fliers Who Savaged Hitler's Wehrmacht and the bookstore is affiliated with the Smithsonian National Air & Space Museum.A bulls-eye.PW article, Bookstore Sells Half of All Copies of WWII Book.