@misc{indiciae08e98c039b02,
  title = {Radioactivity of coal and associated rocks in the anthracite fields of eastern Pennsylvania},
  author = {Stewart Wiliiam Welch},
  year = {1953},
  doi = {10.3133/tei348},
  url = {https://pubs.usgs.gov/publication/tei348},
  note = {Source identifier: tei348}
}