Author(s):
1. Ivana Jovanović, Mining and Metallurgy Institute Bor, Serbia
2. Jasmina Nešković, Mining institute, Belgrade, Serbia, Serbia
3. Slađana Krstić, Mining and Metallurgy Institute Bor, Serbia
4. Milenko Ljubojev, Mining and Metallurgy Institute Bor, Serbia
5. Srđana Magdalinović, Mining and Metallurgy Institute Bor, Serbia

Abstract