1. Review of Fundamentals of Mid-Tertiary Stratigraphical Correlation;Beckamann,1962
2. Planktonic Foraminifera from the Oligocene-Miocene Cipero and Lengua Formations of Trinidad, B.W.I.;Bolli,1957
3. Zonation of Cretaceous to Pliocene marine sediments based on planktonic Foraminifera;Bolli;Bol. Inform., Asoc. Venzolana Geol., Mineria Petrol.,1966
4. Fundamentals of Mid-Tertiary Stratigraphical Correlation;Eames,1962