Author(s):
1. Zdenka Stojanovska, Faculty of Medical Sciences, Goce Delčev University Stip, Macedonia
2. Zora S. Zunić, University of Belgrade, Vinča Institute of Nuclear Sciences, Serbia, Serbia
3. Zoran Ćurguz, Saobraćajni fakultet Doboj, Republic of Srpska, Bosnia and Herzegovina
4. Predrag Kolarž, Institute of Physics, University of Belgrade, , Serbia
5. Ivan Boev, Faculty of natural and technical sciences, Macedonia
6. Blazo Boev, Faculty of natural and technical sciences, Macedonia