@misc{indiciae3b5540ee0412,
  title = {Distribution of minor elements in coal beds of the Eastern Interior region},
  author = {Peter Zubovic and Taisia Maximovna Stadnichenko and Nola B. Sheffey},
  year = {1964},
  doi = {10.3133/b1117b},
  url = {https://pubs.usgs.gov/publication/b1117B},
  note = {Source identifier: b1117B}
}