1. Departement of Mathematics, Freres Mentouri Constantinel University, Algeria
2. LMAM Laboratory and Department of Mathematics, Mohamed Seddik Ben Yahia University, Jijel, Algeria
3. Departement of Mathematics, Colonel El-Hadj Lakhdar University, Batna, Algeria
4. Department of Economics, Faculty of Economics, Administrative and Social Sciences, Hasan Kalyoncu University, TR-27410 Gaziantep, Turkey