@misc{indiciae9a7ced129090,
  title = {Auto-Gopher: A Wire-Line Rotary-Hammer Ultrasonic Drill},
  author = {Badescu, Mircea and Sherrit, Stewart and Bao, Xiaogi and Bar-Cohen, Yoseph and Chen, Beck},
  year = {2011},
  url = {https://ntrs.nasa.gov/citations/20120004210},
  note = {Source identifier: 20120004210}
}