@misc{indiciaebcb4f5077a39,
  title = {Radium concentrations in ground water of the Chickies Formation, southeastern Pennsylvania, 1986-87},
  author = {L. DeWayne Cecil},
  year = {1989},
  doi = {10.3133/ofr87232},
  url = {https://pubs.usgs.gov/publication/ofr87232},
  note = {Source identifier: ofr87232}
}