@misc{indiciae7ae2ca60a7cd,
  title = {Geologic and hydrologic studies in the Birmingham red-iron-ore district, Alabama},
  author = {T.A. Simpson},
  year = {1965},
  doi = {10.3133/pp473c},
  url = {https://pubs.usgs.gov/publication/pp473C},
  note = {Source identifier: pp473C}
}