@misc{indiciae969faabc0feb,
  title = {Documentation of data format and content to accompany magnetic tape copies of various data files of the National Coal Resources Data System (NCRDS); ECOAL, WCOAL, NEWCOAL, BMALYT, and USCHEM},
  author = {M. Devereux Carter and Antoinette L. Medlin and Kathleen K. Krohn},
  year = {1981},
  doi = {10.3133/ofr811079},
  url = {https://pubs.usgs.gov/publication/ofr811079},
  note = {Source identifier: ofr811079}
}