@misc{indiciaef76591215574,
  title = {Relations of biological indicators to nutrient data for lakes and streams in Pennsylvania and West Virginia, 1990-98},
  author = {Robin A. Brightbill and Edward H. Koerkle},
  year = {2003},
  doi = {10.3133/wri034033},
  url = {https://pubs.usgs.gov/publication/wri034033},
  note = {Source identifier: wri034033}
}