@misc{indiciae2c0660f9bf87,
  title = {Chemistry and origin of minor and trace elements in selected vitrinite concentrates from bituminous and anthracitic coals},
  author = {C.A. Palmer and P.C. Lyons},
  year = {1990},
  doi = {10.1016/0166-5162(90)90035-w},
  url = {https://pubs.usgs.gov/publication/70015763},
  note = {Source identifier: 70015763}
}