1. Department of Mathematics, National University of Modern Languages (NUML), Islamabad (Rawalpindi Campus), Pakistan
2. Department of Mathematics, School of Science, University of Management and Technology, Lahore, Pakistan
3. Department of Mathematics, COMSATS University Islamabad, Attock Campus, Pakistan
4. Faculty of Ocean Engineering Technology and Informatics, University Malaysia Terengganu, Teregganu, Malaysia