Author(s):
1. Aleksej Milošević, Rudarski fakultet Prijedor, Republic of Srpska, Bosnia and Herzegovina
2. Aleksandar Grubić, Rudarski institut Prijedor, e-mail Save Kovačevića bb, Prijedor, Republic of Srpska, Bosnia and Herzegovina
3. Ranko Cvijić, Republic of Srpska, Bosnia and Herzegovina
4. Miodrag Čelebić, Mining institute, Belgrade, Serbia, Republic of Srpska, Bosnia and Herzegovina

Abstract