Reference
Volker Ebbighausen, Ralph Thomas Becker, Jürgen Bockwinkel (2002): Morphometric Analyses and Taxonomy of Oxyconic Goniatites (Paratornoceratinae n.subfam.) from the Early Famennian of the Tafilalt (Anti-Atlas, Morocco) – Abhandlungen der Geologischen Bundesanstalt in Wien – 57: 167 - 180.