@misc{indiciaea7ee67529504,
  title = {Bedrock geology, altitude of base, and 1980 saturated thickness of the high plains aquifer in parts of Colorado, Kansas, Nebraska, New Mexico, Oklahoma, South Dakota, Texas, and Wyoming},
  author = {John B. Weeks and Edwin D. Gutentag},
  year = {1981},
  doi = {10.3133/ha648},
  url = {https://pubs.usgs.gov/publication/ha648},
  note = {Source identifier: ha648}
}