@misc{indiciaef36af3aa7e6f,
  title = {U.S. Geological Survey toxic substances hydrology program, surface-water contamination; proceedings of the technical meeting, Denver, Colorado, February 2-4, 1987},
  author = {G. E. Mallard},
  year = {1988},
  doi = {10.3133/ofr87764},
  url = {https://pubs.usgs.gov/publication/ofr87764},
  note = {Source identifier: ofr87764}
}