Borges, V.M., Athayde, G.B. and Reginato, P.A.R. 2017. Evaluation of natural vulnerability to contamination of Serra Geral aquifer system In Paraná – Brazil. Águas Subterrâneas. 31, 4 (Oct. 2017), 327–337. DOI:https://doi.org/10.14295/ras.v31i4.28857.