TY  - BOOK
CN  - NAS 1.55:
CY  - [Washington] :
CY  - Springfield, Va. :
DA  - 1978.
ID  - 180249
KW  - Helicopters
KW  - Acoustical engineering
KW  - Noise control
PB  - National Aeronautics and Space Administration,    Scientific and Technical Information Office ;
PB  - for sale by the National Technical Information Service,
PP  - [Washington] :
PP  - Springfield, Va. :
PY  - 1978.
T1  - Helicopter acoustics :proceedings of an International           Specialists Symposium sponsored by the American Helicopter Society, Washington, D.C.; the U.S. Army Research Office, Durham, North Carolina; and the Langley    Research Center, Hampton, Virginia, and held at Langley Research Center, May 22-24, 1978.
TI  - Helicopter acoustics :proceedings of an International           Specialists Symposium sponsored by the American Helicopter Society, Washington, D.C.; the U.S. Army Research Office, Durham, North Carolina; and the Langley    Research Center, Hampton, Virginia, and held at Langley Research Center, May 22-24, 1978.
ER  -