@misc{indiciae9beef590d89c,
  title = {Field geology of Tertiary coals in the Powder River Basin, Wyoming and Montana},
  author = {R. M. Flores and Peter D. Warwick and T.A. Moore and J. N. Weaver},
  year = {1987},
  url = {https://pubs.usgs.gov/publication/70194831},
  note = {Source identifier: 70194831}
}