@misc{indiciae9420596d744d,
  title = {Mathematical model of gamma-ray spectrometry borehole logging for quantitative analysis},
  author = {Ulrich Schimschal},
  year = {1981},
  doi = {10.3133/ofr81402},
  url = {https://pubs.usgs.gov/publication/ofr81402},
  note = {Source identifier: ofr81402}
}