1. Department of Mathematics, Taibah University, Al-Madinah Al-Munawarah, Saudi Arabia + Department of Mathematics, Faculty of Science, Mansoura University, Mansoura, Egypt
2. Department of Mathematics, Qassim University, Buraidah, Saudi Arabia
3. Department of Mathematics, Cankaya University, Balgat, Ankara, Turkey + Department of Medical Research, China Medical University, Taichung, Taiwan + Institute of Space Sciences, Bucharest, Romania
4. Department of Mathematics, Firat University, Elazig, Turkey