@misc{indiciaeab1c684a1a06,
  title = {Lignite geology of southeast Williams County, North Dakota},
  author = {John M. Spencer},
  year = {1978},
  doi = {10.3133/ofr78168},
  url = {https://pubs.usgs.gov/publication/ofr78168},
  note = {Source identifier: ofr78168}
}