Reference

Thomas Gaßner, Norbert Micklich, Rolf Kohring, Gabriele Gruber (2002): Turtles (Testudines, Geoemydidae,"Ocadia" sp.) with Three-dimensionally Preserved Remains of Internal Organs from the Middle Eocene of Grube Messel (Hessen, Germany) – Kaupia - Darmstädter Beiträge zur Naturgeschichte – 11: 111 - 123.