@misc{indiciae5f73bce145de,
  title = {The Square Buttes coal field, Oliver and Mercer Counties, North Dakota},
  author = {William D. Johnson and Robert Paul Kunkel},
  year = {1959},
  doi = {10.3133/b1076},
  url = {https://pubs.usgs.gov/publication/b1076},
  note = {Source identifier: b1076}
}