Ibaraki, Masako (2000): Planktonic foraminifers off Costa Rica in the East Pacific Ocean - biostratigraphic and chronostratigraphic analyses. In: Silver, EA; Kimura, G; Shipley, TH (eds.) Proceedings of the Ocean Drilling Program, Scientific Results, College Station, TX (Ocean Drilling Program), 170, 1-58, doi:10.2973/odp.proc.sr.170.001.2000