@misc{indiciaeb9a39acea4c1,
  title = {Conversion of geologic quadrangle maps to geologic coverages},
  author = {Joseph F. Connell and William R. Barron and Reavis L. Mitchell},
  year = {1994},
  doi = {10.3133/ofr94359},
  url = {https://pubs.usgs.gov/publication/ofr94359},
  note = {Source identifier: ofr94359}
}