@misc{indiciaecb4028a9b3f9,
  title = {Modes of occurrence of potentially hazardous elements in coal: Levels of confidence},
  author = {Robert B. Finkelman},
  year = {1994},
  doi = {10.1016/0378-3820(94)90169-4},
  url = {https://pubs.usgs.gov/publication/70017616},
  note = {Source identifier: 70017616}
}