@misc{indiciae72b73c9bc8b9,
  title = {Mineral Commodity Summaries 2011},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey},
  year = {2011},
  doi = {10.3133/mineral2011},
  url = {https://pubs.usgs.gov/publication/mineral2011},
  note = {Source identifier: mineral2011}
}