Late Paleocene fossils from the Cerrejón Formation, Colombia, are the earliest record of Neotropical rainforestDOI: info:10.1073/pnas.0905130106v. 106No. 44National Academy of Sciences (U.S.)18627–18632
Wing, Scott L., Herrera, Fabiany, Jaramillo, Carlos A., Gómez-Navarro, Carolina, Wilf, Peter, and Labandeira, Conrad C. 2009. "Late Paleocene fossils from the Cerrejón Formation, Colombia, are the earliest record of Neotropical rainforest." Proceedings of the National Academy of Sciences of the United States of America, 106, (44) 18627–18632. https://doi.org/10.1073/pnas.0905130106.