@misc{indiciae4cf6e2d4e928,
  title = {Structure contour map of the Pondera oil field, Montana},
  author = {Charles Edgar Erdmann and B.K. Koskinen},
  year = {1952},
  doi = {10.3133/ofr5241},
  url = {https://pubs.usgs.gov/publication/ofr5241},
  note = {Source identifier: ofr5241}
}