@misc{indiciae08df06d80f42,
  title = {Land and natural resource information and some potential environmental effects of surface mining of coal in the Gillette area, Wyoming},
  author = {William Richard Keefer and R. F. Hadley},
  year = {1976},
  doi = {10.3133/cir743},
  url = {https://pubs.usgs.gov/publication/cir743},
  note = {Source identifier: cir743}
}