1. Department of Basic Sciences, University of Engineering and Technology, Taxila, Pakistan
2. Department of Mathematics, Quaid-i-Azam University, Islamabad, Pakistan
3. Department of Mathematics, National University of Modern Languages, Islamabad, Pakistan
4. Department of Mathematics, Shaheed Benazir Bhutto University, Sheringal Upper Dir, Pakistan
5. Department of Mathematics, School of Engineering, University of Petroleum & Energy Studies (UPES), Bidholi Dehradun, Uttarakhand, India