Sharp (Martin) DH-A History of de Havilland 1982; Ellison (Norman) British Gliders and Sailplanes 1922-1970 1971; Robertson (Bruce) Sopwith- The Man and His Aircraft 1970; Andrews (Allen) Back to the Drawing Board- The Evolution of Flying Machines 1977; and a quantity of BAC 1-11 manuals and others. (a lot)