@misc{indiciae14f123300f05,
  title = {Mineral resources of the Appalachian region},
  author = {Members of the Engineering Geology and Ground Water Branches, U.S. Geological Survey and U.S. Bureau of Mines},
  year = {1968},
  doi = {10.3133/pp580},
  url = {https://pubs.usgs.gov/publication/pp580},
  note = {Source identifier: pp580}
}