@misc{indiciaee56ad32c97b0,
  title = {Generalized altitude and configuration of the base of the High Plains regional aquifer, northwestern Oklahoma},
  author = {John S. Havens},
  year = {1981},
  doi = {10.3133/ofr811117},
  url = {https://pubs.usgs.gov/publication/ofr811117},
  note = {Source identifier: ofr811117}
}