@misc{indiciaeb171e29e021a,
  title = {General introduction and hydrologic definitions},
  author = {W. B. Langbein and Kathleen T. Iseri},
  year = {1960},
  doi = {10.3133/wsp1541a},
  url = {https://pubs.usgs.gov/publication/wsp1541A},
  note = {Source identifier: wsp1541A}
}