@misc{indiciae7dcdf17802e1,
  title = {USGS FM cassette seismic-refraction recording system},
  author = {J.M. Murphy},
  year = {1988},
  doi = {10.3133/ofr88570},
  url = {https://pubs.usgs.gov/publication/ofr88570},
  note = {Source identifier: ofr88570}
}