@misc{indiciae4e04abf38d78,
  title = {Radioactivity of Pennsylvanian black shales and coals in Kansas and Oklahoma},
  author = {Archibald L. Slaughter},
  year = {1945},
  doi = {10.3133/tei18},
  url = {https://pubs.usgs.gov/publication/tei18},
  note = {Source identifier: tei18}
}