1. Department of Mathematics, College of Science, University of Ha'il, Ha'il 55473, Saudi Arabia; Email: mo.abdelkader@uoh.edu.sa
2. Laboratory of pure and applied mathematics, University of Amar Telidji, Laghouat, Algeria; Email: f.yazid@lagh-univ.dz (F.Y.), fs.djeradi@lagh-univ.dz (F.S.D.)
3. Mathematics Department, Faculty of Science, King Khalid University, P.O. Box 9004, Abha 61413, Saudi Arabia; Email: mblgasim@kku.edu.sa
4. Department of Mathematics, Faculty of Sciences, University of Ibn Khladoun, BP P 78 Zaaroura, Tiaret 14000, Algeria; Email: tayeb.mahrouz@univ-tiaret.dz