@misc{indiciae8fb63369b21b,
  title = {Distribution of minor elements in coals of the Appalachian region},
  author = {Peter Zubovic and Taisia Maximovna Stadnichenko and Nola B. Sheffey},
  year = {1966},
  doi = {10.3133/b1117c},
  url = {https://pubs.usgs.gov/publication/b1117C},
  note = {Source identifier: b1117C}
}