@misc{indiciae44fa9d0905a1,
  title = {Bedrock topography of west-central Iowa},
  author = {R.E. Hansen and D. L. Runkle},
  year = {1984},
  doi = {10.3133/ofr84731},
  url = {https://pubs.usgs.gov/publication/ofr84731},
  note = {Source identifier: ofr84731}
}