1. Institute of Earth Sciences, Faculty of Natural Sciences, University of Silesia in Katowice, Będzińska 60, 41-200 Sosnowiec, Poland
2. Department of Systems and Computer Networks, Faculty of Computer Science and Telecommunications, Wrocław University of Science and Technology, Wyspiański Wybrzeże 27, 50-370 Wrocław, Poland
3. Institute of Social and Economic Geography and Spatial Management, Faculty of Natural Sciences, University of Silesia in Katowice, Będzińska 60, 41-200 Sosnowiec, Poland