@misc{indiciae0ab74dad7587,
  title = {Preliminary map of titanium provinces in the conterminous United States},
  author = {Edwin Wilson Tooker and Eric R. Force},
  year = {1980},
  doi = {10.3133/ofr79576k},
  url = {https://pubs.usgs.gov/publication/ofr79576K},
  note = {Source identifier: ofr79576K}
}