Reference

Volker Dietze, Günter Schweigert, Gerd Dietl, Wolfgang Auer, Wolfgang Dangelmaier, Roger Furze, Stefan Gräbenstein, Michael Kutz, Elmar Neisser, Erich Schneider, Dietmar Schreiber (2010): Rare Middle Jurassic ammonites of the families Erycitidae, Otoitidae and Stephanoceratidae from southern Germany – Zitteliana Serie A – 50: 71 - 88.