@misc{indiciaed7c8762cd2d1,
  title = {Helicopter noise prediction - The current status and future direction},
  author = {Brentner, Kenneth S. and Farassat, F.},
  year = {1992},
  url = {https://ntrs.nasa.gov/citations/19930035205},
  note = {Source identifier: 19930035205}
}