1. Department of Basic Sciences and Humanities, Muhammad Nawaz Sharif University of Engineering and Technology, Multan, Pakistan
2. Center for Advanced Studies in Pure and Applied Mathematics (CASPAM), Bahauddin Zakariya University, Multan, Pakistan
3. Department of Mathematics, Capital University of Science and Technology (CUST), Islamabad, Pakistan
4. Department of Mathematics, Faculty of Science, Islamic University of Madinah, Medina, Saudi Arabia