@misc{indiciaed7806b10c8a5,
  title = {DONAR - A computer processing system to extend ultrasonic pulse-echo testing.},
  author = {Lees, S. and Gerhard, F. B. and Barber, F. E. and Cheney, S. P.},
  year = {1973},
  url = {https://ntrs.nasa.gov/citations/19730052646},
  note = {Source identifier: 19730052646}
}