@misc{indiciae73282f33363e,
  title = {Operator's manual for a four-film computer-based, sonic digitizing table to locate earthquakes},
  author = {Mary C. Astrue and J.R. Pelton and W.H. Lee and R.A. Page},
  year = {1983},
  doi = {10.3133/ofr83319},
  url = {https://pubs.usgs.gov/publication/ofr83319},
  note = {Source identifier: ofr83319}
}