1. Department of Mathematics and Natural Sciences, Prince Mohammad Bin Fahd University, Al Khobar, Saudi Arabia
2. Department of Mathematics, University of Sargodha, Sargodha, Pakistan
3. School of Mathematical Sciences, Universiti Sains Malaysia, Pulau Pinang, Malaysia
4. Department of Mathematics and Statistics, College of Science, Taif University, Taif, Saudi Arabia
5. Department of Mathematics, Virtual University of Pakistan, Lahore, Pakistan