Reference

Philip D. Gingerich, Mohammed Sameh M. Antar, Iyad S. Zamout (2011): Projection stratigraphy of the upper Eocene Gehannam, Birket Qarun, and Qasr el-Sagha formations and their fossil whales at the Wadi Al Hitan World Heritage Site, western Fayum Province (Egypt) – Berichte der Geologischen Bundesanstalt – 85: 82.