1. Department of Applied Mathematics and Informatics, Faculty of Mining and Geology, University of Belgrade, Belgrade, Serbia
2. Geology Department, Jaroslav Černi Water Institute, Belgrade + Faculty of Technical Sciences, University of Novi Sad, Novi Sad, Serbia
3. Department of Mathematics and Physics, Faculty of Pharmacy, University of Belgrade, Belgrade, Serbia
4. Faculty of Transport and Traffic Engineering, University of Belgrade, Belgrade, Serbia