@misc{indiciae86b3f67489a8,
  title = {Slide set describing aspects of the origin of coal, coal mining, and peat formation},
  author = {R.W. Stanton and B.S. Pierce},
  year = {1991},
  doi = {10.3133/ofr91390},
  url = {https://pubs.usgs.gov/publication/ofr91390},
  note = {Source identifier: ofr91390}
}