Bijl, Peter K.; Houben, Alexander J. P.; Schouten, Stefan; Bohaty, Steven M.; Sluijs, Appy; Reichart, Gert-Jan; Sinninghe Damste, Jaap S.; Brinkhuis, Henk (2010): Transient middle Eocene atmospheric CO (sub 2) and temperature variations. American Association for the Advancement of Science, Washington, DC, United States, Science, 330 (6005), 819-821, georefid:2011-008029