@misc{indiciae25aa7102139c,
  title = {Preliminary digital Quaternary geologic map data for Indiana},
  author = {D. R. Soller and Wai-See Moy},
  year = {1993},
  doi = {10.3133/ofr93268a},
  url = {https://pubs.usgs.gov/publication/ofr93268A},
  note = {Source identifier: ofr93268A}
}