@misc{indiciaeb6a9625d24fd,
  title = {Map showing structure contours on the top of the upper Jurassic Morrison Formation, Powder River basin, Wyoming and Montana},
  author = {B.L. Crysdale},
  year = {1991},
  doi = {10.3133/mf2140c},
  url = {https://pubs.usgs.gov/publication/mf2140C},
  note = {Source identifier: mf2140C}
}