@misc{indiciae6aea37c305ba,
  title = {Ultrasonic pulsed phase locked loop interferometer for bolt load measurements},
  author = {Allison, S. G. and Clendenin, C. G.},
  year = {1989},
  url = {https://ntrs.nasa.gov/citations/19910035041},
  note = {Source identifier: 19910035041}
}