@misc{indiciaec566dc4e40bb,
  title = {The lignite field of northwestern South Dakota},
  author = {Dean Eddy Winchester and Charles Joseph Hares and Edwin Russell Lloyd and E.M. Parks},
  year = {1916},
  doi = {10.3133/b627},
  url = {https://pubs.usgs.gov/publication/b627},
  note = {Source identifier: b627}
}