@misc{indiciaeed698024397f,
  title = {SEM-EDX and isotope characterization of the organic sulfur in macerals and chars in Illinois Basin coals},
  author = {I. Demir and R.D. Harvey and Keith C. Hackley},
  year = {1993},
  doi = {10.1016/0146-6380(93)90043-b},
  url = {https://pubs.usgs.gov/publication/70018208},
  note = {Source identifier: 70018208}
}