@misc{indiciaefe431b26ff09,
  title = {Ground-water resources in the Libby area, northwestern Montana},
  author = {Arnold J. Boettcher and Kathleen R. Wilke},
  year = {1977},
  doi = {10.3133/ofr77397},
  url = {https://pubs.usgs.gov/publication/ofr77397},
  note = {Source identifier: ofr77397}
}