1. Department of Mathematical Sciences, Faculty of Science, Islamic University of Madina, Madinah, Saudi Arabia
2. Department of Mathematics, Faculty of Science, Zagazig University, Zagazig, Egypt
3. Department of Mathematics, Faculty of Science, Taibah University, Madinah, Saudi Arabia
4. Arab Academy for Science, Technology and Maritime Transport, Alexandria, Egypt
5. National Committee for Mathematics, Academy of Scientific Research and Technology, Cairo, Egypt