@misc{indiciaec252fc91d610,
  title = {Mineral resources of the United States, 1921: Part I - Metals},
  author = {Gerald Francis Loughlin},
  year = {1924},
  doi = {10.3133/70175845},
  url = {https://pubs.usgs.gov/publication/70175845},
  note = {Source identifier: 70175845}
}