@misc{indiciae20206ad17a01,
  title = {Tests of a hole-to-hole acoustic pulse measurement system},
  author = {James H. Scott},
  year = {1981},
  doi = {10.3133/ofr811087},
  url = {https://pubs.usgs.gov/publication/ofr811087},
  note = {Source identifier: ofr811087}
}