Petzold, A.; Vargas-Ramírez, M.; Kehlmaier, C.; Vamberger, M.; Branch, W. R.; Preez, L. D.; Hofmeyr, M. D.; Meyer, L.; Schleicher, A.; Široký, P.; Fritz, U. A Revision of African Helmeted Terrapins (Testudines: Pelomedusidae: Pelomedusa), With Descriptions of Six New Species. Zootaxa 2014, 3795, 523–548.