Reference
Silvia Ortiz, Aitor Payros, Xabier Orue-Etxebarria, Estibaliz Apellaniz, E. Molina (2011): A short-lived warming event in the middle Eocene of the Gorrondatxe section (Western Pyrenees): evidence of a Lutetian Thermal Restoration – Berichte der Geologischen Bundesanstalt – 85: 121.