@misc{indiciaefb234ac0c663,
  title = {Guide to the use of PACER, the data retrieval and update system for the National Coal Resources Data System (NCRDS)},
  author = {K.K. Krohn and M.A. Carey and M.D. Carter and A.L. Medlin},
  year = {1982},
  doi = {10.3133/ofr82291},
  url = {https://pubs.usgs.gov/publication/ofr82291},
  note = {Source identifier: ofr82291}
}