1. 1 Department of Mathematics , Khazar University , Baku Azerbaijan ; Research Center of Econophysics , UNEC-Azerbaijan State University of Economics , Baku Azerbaijan
2. 2 Department of Mathematics , Mehmet Akif Ersoy University , Burdur Turkey ; Research Center of Econophysics , UNEC-Azerbaijan State University of Economics , Baku Azerbaijan
3. 3 Department of Mathematics , Khazar University Baku Azerbaijan