@misc{indiciae658381a063e2,
  title = {Strippable lignite deposits, Slope and Bowman Counties, North Dakota},
  author = {Roy Clark Kepferle and W.C. Culbertson},
  year = {1955},
  doi = {10.3133/b1015e},
  url = {https://pubs.usgs.gov/publication/b1015E},
  note = {Source identifier: b1015E}
}