Lobo Ferreira, J.P., Krijgsman, B. y Feseker, T. 2004. Models for wellhead protection in regional unconfined aquifers and stratified aquifers. Geofísica Internacional. 43, 4 (oct. 2004), 651–659. DOI:https://doi.org/10.22201/igeof.00167169p.2004.43.4.849.