1. Helicopter Theory;Johnson,1980
2. Developments in rotary wing aircraft aerodynamics;Cheeseman;Vertica,1982
3. Rotor wakes-Key to performance prediction;Landgrebe,1972
4. Aerodynamic technology for advanced rotorcraft—Part I;Landgrebe,1976
5. Formulation and solution of rotary-wing aeroelastic problems;Friedmann,1981