@misc{indiciae3c59ee867b29,
  title = {Secrets in Stone},
  author = {David Donnenfield Productions and Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1998},
  doi = {10.3133/ofr9827},
  url = {https://pubs.usgs.gov/publication/ofr9827},
  note = {Source identifier: ofr9827}
}