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\bibitem{Troeger_etal2004} Tr{\"o}ger, U., Dias, C. L., Guillaumon, J. R., Iritani, M. A., K{\"u}lls, C., \& Schuler, G. (2004). Remarks and new data about the recharge of the Guarani Aquifer System. In \textit{XXXIII IAH Congress, Abstracts, IAH, Mexico}.

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