1. Department of Mathematics, Faculty of Science, Jiangsu University, Jiangsu, P. R. China
2. Department of Mathematics, Obour Institutes, Cairo 11828, Egypt
3. Department of Physics, College of Sciences, University of Bisha, P.O. Box 344, 61922 Bisha, Saudi Arabia
4. Physics Department, Faculty of Science, Al-Azhar University, 71524 Assiut, Egypt
5. Physics Department, Faculty of Science, University of Jeddah, Jeddah, Saudi Arabia
6. Department of Basic Science, Higher Technological Institute Campus, 10th of Ramadan, Sharqia, Egypt