1. Polish Geological Institute – National Research Institute Rakowiecka 4 00‐975 Warsaw Poland
2. Department of Geophysics, Institute of Oceanography University of Gdansk al. Piłsudskiego 46 81‐378 Gdynia Poland
3. Institute of Geological Sciences, Polish Academy of Sciences Research Centre in Warsaw, ING PAN Twarda St. 51/55 PL‐00818 Warsaw Poland
4. Institute of Geography and Regional Studies Pomeranian University in Słupsk Partyzantów St. 27 Słupsk PL‐76‐200 Poland
5. University of Warsaw Faculty of Geology Warsaw Poland
6. Pope John Paul 2nd State School of Higher Education Faculty of Economics Sciences Sidorska 95/97, 21‐500 Poland