@misc{indiciae61b1df691b53,
  title = {Local variation in background water quality.},
  author = {B W Webb and D E Walling},
  year = {1974},
  doi = {10.1016/0048-9697(74)90024-2},
  url = {https://pubmed.ncbi.nlm.nih.gov/4439007/},
  note = {Source identifier: 4439007}
}