@misc{indiciae58a3729ac20b,
  title = {Assessment of nitrate contamination of the upper aquifer in the Manati-Vega Baja area, Puerto Rico},
  author = {Carlos Conde-Costas and Fernando Gómez-Gómez},
  year = {1999},
  doi = {10.3133/wri994040},
  url = {https://pubs.usgs.gov/publication/wri994040},
  note = {Source identifier: wri994040}
}