Dating of the Cretaceous Une Formation, Colombia and the relationship with the Albian-Cenomanian African-South American microfloral province

• G.F.W. Herngreen, H. Duenas Jimenez

• Review of Palaeobotany and Palynology, December 1990, Elsevier
• DOI: 10.1016/0034-6667(90)90046-l