@misc{indiciae064d36eaef41,
  title = {Geologic and structure map, with contours on top of the Pierre Shale, for the south half of the Powder River basin, northeastern Wyoming},
  author = {N.M. Denson and M.L. Gibson and G.L. Sims},
  year = {1993},
  doi = {10.3133/i2343b},
  url = {https://pubs.usgs.gov/publication/i2343B},
  note = {Source identifier: i2343B}
}