1. Department of Mathematics, Faculty of Exact Sciences, Hamma Lakhdar University, 39000 El-Oued, Algeria, Laboratoire “TPFA”, ENS, BP 92 Kouba, Algiers 16006, Algeria
2. Department of Mathematics, Faculty of Sciences, Imam Mohammad Ibn Saud Islamic University (IMSIU), PB 90950, Riyadh 11623, Saudi Arabia
3. Laboratoire “TPFA”, ENS, BP 92 Kouba, Algiers 16006, Algeria