@misc{indiciaeb1134210ebaa,
  title = {Modes of occurrence of trace elements in samples from a coal cleaning plant},
  author = {Curtis A. Palmer and Allan Kolker and Robert B. Finkelman and K.C. Kolb and Stanley J. Mroczkowski and S.S. Crowley and H. E. Belkin and J. H. Bullock and J. M. Motooka},
  year = {1997},
  doi = {10.3133/ofr97732},
  url = {https://pubs.usgs.gov/publication/ofr97732},
  note = {Source identifier: ofr97732}
}