@misc{indiciae17b6f01ccb05,
  title = {Origin of thick Lower Tertiary coal beds in the Powder River Basin, Wyoming and Montana— Some paleogeographic constraints},
  author = {David A. Seeland},
  year = {1993},
  doi = {10.3133/b1917q},
  url = {https://pubs.usgs.gov/publication/b1917Q},
  note = {Source identifier: b1917Q}
}