1. Improvements in or relating to damping of oscillation-checking devices;Carter,1929
2. Means adapted to reduce the torsional oscillations of crankshafts;Sarazin,1931
3. Pendulum counterweight;Chilton,1935
4. The elements of pendulum dampers;Zdanowich;Proc. Inst. Mech. Eng.,1940
5. J.-G. Duh, M. Wenyong, Development of Monofilar Rotor Hub Vibration Absorber, Tech. rep., 1983.