1. Mineral and Economy Research Institute of the Polish Academy of Sciences, Wybickiego 7A, 31-261 Cracow, Poland
2. Central Mining Institute, Plac Gwarków 1, 40-166 Katowice, Poland
3. Faculty of Civil Engineering, Cracow University of Technology, Warszawska 24, 31-155 Cracow, Poland
4. Faculty of Geology, University of Warsaw, Krakowskie Przedmieście 26/28, 00-927 Warsaw, Poland