@misc{indiciaefc170a8e6ad4,
  title = {Metalliferous black shales and related ore deposits; program and abstracts},
  author = {Richard I. Grauch and Joel S. Leventhal},
  year = {1989},
  doi = {10.3133/cir1037},
  url = {https://pubs.usgs.gov/publication/cir1037},
  note = {Source identifier: cir1037}
}