1. Alfred Wegener Institute Helmholtz Centre for Polar and Marine Research Potsdam Germany
2. University of Potsdam Institute of Geosciences Potsdam Germany
3. Department of Geosciences University of Oslo Oslo Norway
4. GFZ German Research Centre for Geosciences Section Geomicrobiology Potsdam Germany
5. University of Potsdam, Institute of Biogeochemistry and Biology Potsdam Germany
6. Melnikov Permafrost Institute Siberian Branch of the Russian Academy of Sciences Yakutsk Russia