@misc{indiciaed329b5c08b35,
  title = {Coal Thickness Gauging Using Elastic Waves},
  author = {Nazarian, Soheil and Bar-Cohen, Yoseph},
  year = {1999},
  url = {https://ntrs.nasa.gov/citations/20000060849},
  note = {Source identifier: 20000060849}
}