1. Steinmann-Institut; Universität Bonn; Bonn Germany
2. Department of Earth Sciences; Stellenbosch University; Stellenbosch South Africa
3. School of Earth Sciences; University of Melbourne; Melbourne Victoria Australia
4. Department of Geology and Paleontology; University St. Kliment Ohridski; Sofia Bulgaria
5. Institute of Geosciences; Jena University; Jena Germany