1. Department of Mathematics and Statistics; University of Victoria; Victoria British Columbia V8 W 3R4 Canada
2. Department of Medical Research, China Medical University Hospital; China Medical University; Taichung 40402 Taiwan Republic of China
3. Department of Mathematics; Aligarh Muslim University; Aligarh 202002 Uttar Pradesh India
4. Operator Theory and Applications Research Group, Department of Mathematics, Faculty of Science; King Abdulaziz University; PO Box 80203 Jeddah 21589 Kingdom of Saudi Arabia
5. Department of Mathematics, Faculty of Science; King Abdulaziz University; PO Box 80203 Jeddah 21589 Kingdom of Saudi Arabia