@misc{indiciae98e253652c96,
  title = {Coal investigation in the Saline-Gallatin field, Illinois, and the adjoining area. The Arkansas coal field},
  author = {F.W. DeWolf and A. J. Collier},
  year = {1907},
  doi = {10.3133/b316b},
  url = {https://pubs.usgs.gov/publication/b316B},
  note = {Source identifier: b316B}
}