@misc{indiciaed1413c8d505d,
  title = {Quality of surface water in the coal-mining region, southwestern Indiana, March and May 1979},
  author = {Danny E. Renn and Stephen E. Ragone and William G. Wilber},
  year = {1980},
  doi = {10.3133/ofr80970},
  url = {https://pubs.usgs.gov/publication/ofr80970},
  note = {Source identifier: ofr80970}
}