1. Department of Mathematics, Faculty of Science, Assiut University, Assiut, Egypt
2. Department of Mathematics, Faculty of Science, Taif University, P. O. Box 11099, Taif 21944, Saudi Arabia
3. Department of Mathematics, Pan African Institute of Basic Science Technology and Innovation, Nairobi, Kenya
4. College of Business Administration in Hotat Bani Tamim, Prince Sattam Bin Abdulaziz University, Al-Kharj, Saudi Arabia