@misc{indiciae1c51702aaa1d,
  title = {Petrography and geochemistry of selected lignite beds in the Gibbons Creek mine (Manning Formation, Jackson Group, Paleocene) of east-central Texas},
  author = {Peter D. Warwick and Sharon S. Crowley and Leslie F. Ruppert and James Pontolillo},
  year = {1997},
  doi = {10.1016/s0166-5162(97)00028-1},
  url = {https://pubs.usgs.gov/publication/70019290},
  note = {Source identifier: 70019290}
}