@misc{indiciae57ff8f4d91c5,
  title = {Piezoelectric loudspeaker},
  author = {Regan, Curtis Randall and Jalink, Antony, Jr. and Hellbaum, Richard F. and Rohrbach, Wayne W.},
  year = {1994},
  url = {https://ntrs.nasa.gov/citations/19950007697},
  note = {Source identifier: 19950007697}
}