@misc{indiciae2e8d37da398e,
  title = {Mineral Commodity Summaries 1997},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {1997},
  doi = {10.3133/mineral1997},
  url = {https://pubs.usgs.gov/publication/mineral1997},
  note = {Source identifier: mineral1997}
}