1. Department of Mathematics, Laboratory of Mathematics, Djillali Liabes University of Sidi Bel Abbes, Sidi Bel Abbes, Algeria
2. Research Unit LaMOS (Modeling and Optimization of Systems), Faculty of Technology, University of Bejaia, Bejaia, Algeria
3. Research Unit LaMOS (Modeling and Optimization of Systems), University of Bejaia, Algeria
4. Laboratory of Mathematics, University of Sidi Bel Abbes, Algeria Abou Bekr Belkaid University of Tlemcen, Tlemcen, Algeria