1. Development of Rotorcraft Interior Noise Control Concepts, Phase I: Definition Study;Yoerkie,1983
2. Identification and Proposed Control of Helicopter Transmission Noise at the Source;Coy,1987
3. Mechanisms of noise transmission through helicopter gearbox support struts;Brennan;J. Vib. Acoust.,1994
4. Helicopter gear noise and its transmission to the cabin;Pollard,1977
5. Recent Langley helicopter acoustics contributions;Morgan,1988