Trends of the nesting activity of the "arribadas" of the olive ridley (Lepidochelys olivacea, Eschscholtz 1829), in the Ostional National Wildlife Refuge (1971-2003). - Gerardo Chaves; Juan Carlos Castro; Juan Ramón Avilés; Mario Alvarado; Rodrigo Morera (Res. Comput. Sci., 2004)