@misc{indiciae2bcbd1f23d8e,
  title = {Groundwater technical procedures of the U.S. Geological Survey},
  author = {William L. Cunningham and Charles W. Schalk},
  year = {2011},
  doi = {10.3133/tm1a1},
  url = {https://pubs.usgs.gov/publication/tm1A1},
  note = {Source identifier: tm1A1}
}