Аутори:
1. Dragana Milosavljević, University of Nis, Faculty of Sciences and Mathematics, , Serbia
2. Драгољуб Мирјанић, Академија наука и умјетности Републике Српске,
Republic of Srpska, Bosnia and Herzegovina
3. Darko Divnić, Академија наука и умјетности Републике Српске,
Republic of Srpska, Bosnia and Herzegovina
4. Tomislav Pavlović, University of Nis, Faculty of Sciences and Mathematics, , Serbia
5. Lana Pantić, University of Nis, Faculty of Sciences and Mathematics, , Serbia
6. Ivana Radonjić, University of Nis, Faculty of Sciences and Mathematics, , Serbia