1. Absolute chronology of the Pliocene-Quaternary sediment sequence of the Bogotá area, Colombia;Andriessen;Quat. Sci. Rev.,1993
2. Tectonic and Climatic Controls on Late Quaternary Sedimentary Processes in a Neotectonic Intramontane Basin (The Pitalito Basin, South Colombia);Bakker,1990
3. Atlas of Seeds and Small Fruits of Northwest-European Plant Species, 3: Salicaceae-Cruciferae;Berggren,1981
4. Pliocene fossil plants from Eastern Bolivia;Berry;Johns Hopkins Univ. Stud. Geol.,1922
5. Saccoglottis, recent and fossil;Berry;Am. J. Sci. 5th Ser.,1922