@misc{indiciaeb7f7f148ba1f,
  title = {Potentiometric surfaces of the upper and lower aquifers, north coast limestone aquifer system, Puerto Rico},
  author = {Robert A. Renken and Fernando Gómez-Gómez},
  year = {1994},
  doi = {10.3133/ofr93499},
  url = {https://pubs.usgs.gov/publication/ofr93499},
  note = {Source identifier: ofr93499}
}