1. Department of Mathematics, College of Science, University of Ha’il, Ha’il 2440, Saudi Arabia
2. Department of Mathematics and Statistics, The University of Lahore, Sargodha 40100, Pakistan
3. University of Massachusetts Chan Medical School (UMASS), 55 Lake Avenue North, Worcester, MA 01655, USA
4. Massachusetts Institute of Technology (MIT), 77 Massachusetts Avenue, Cambridge, MA 02139, USA