Author(s):
1. Marica Dugić, Rafinerija ulja Modriča, Republic of Srpska, Bosnia and Herzegovina
2. Branko Despotović, Rafinerija ulja Modriča, Republic of Srpska, Bosnia and Herzegovina
3. Tatjana Botić, Faculty of Technology Banja Luka, Republic of Srpska, Bosnia and Herzegovina
4. Pero Dugić, Republic of Srpska, Bosnia and Herzegovina