1. Institute of Geology and Palaeontology Univerzita Karlova Albertov 2038/6 128 43 Praha Czech Republic
2. Department of Earth Sciences Institute of Geology, Mineralogy and Geophysics Ruhr‐Universität Bochum Universitätsstraße 150 44801 Bochum Germany
3. Am Hohen Holze 30823 Garbsen Germany