1. Department of Mathematics and Statistics, Riphah International University I-14, Islamabad, Pakistan
2. Department of Mechanics and Engineering Science, Peking University, Beijing, People’s Republic of China
3. Department of Mathematics, COMSATS University Islamabad, Sahiwal, Pakistan
4. Mathematics Department, College of Education for Girls at Al-Qunfudah, Umm Al-Qura University, Mecca, Saudi Arabia
5. Department of Mathematics and Statistics, College of Science, Taif University, Taif, Saudi Arabia
6. Department of Mathematics, College of Science and Humanities in Al-Kharj, Prince Sattam bin Abdulaziz University, Al-Kharj, Saudi Arabia
7. Department of Basic Engineering Science, Faculty of Engineering, Menoufia University, Shebin El-Kom, Egypt
8. Department of Mathematics, College of Sciences, King Khalid University, Abha, Saudi Arabia