@misc{indiciae9d59734ea007,
  title = {Pennsylvanian (Upper Carboniferous) system of Wyoming},
  author = {Edwin K. Maughan},
  year = {1978},
  doi = {10.3133/ofr78377},
  url = {https://pubs.usgs.gov/publication/ofr78377},
  note = {Source identifier: ofr78377}
}