@misc{indiciaeb6181d7d145f,
  title = {Assessment of water quality in streams draining coal-producing areas in Ohio},
  author = {C.L. Pfaff and D.R. Helsel and D.P. Johnson and C.G. Angelo},
  year = {1981},
  doi = {10.3133/wri81409},
  url = {https://pubs.usgs.gov/publication/wri81409},
  note = {Source identifier: wri81409}
}