@misc{indiciaecbb607da1d40,
  title = {Annotated bibliography and index map of sulfur and pyrites deposits in the United States and Alaska (including references to July 1, 1951)},
  author = {Gilbert H. Espenshade and Carl H. Broedel},
  year = {1952},
  doi = {10.3133/cir157},
  url = {https://pubs.usgs.gov/publication/cir157},
  note = {Source identifier: cir157}
}