@misc{indiciae9289c9ed52b7,
  title = {Rotating-blade vortex noise},
  author = {Scheiman, J. and Letko, W. and Shivers, J. P. and Hilton, D. A.},
  year = {1973},
  url = {https://ntrs.nasa.gov/citations/19740039720},
  note = {Source identifier: 19740039720}
}