Umaña V., G. (1998). Characterization of some Golfo Dulce drainage basin rivers (Costa Rica).
Chicago Style aipamenaUmaña V., Gerardo. Characterization of Some Golfo Dulce Drainage Basin Rivers (Costa Rica). 1998.
MLA aipamenaUmaña V., Gerardo. Characterization of Some Golfo Dulce Drainage Basin Rivers (Costa Rica). 1998.
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