[1] Mohi Ud Din Islamic Univ, Dept Math, Nerian Sharif, AJ&K, Pakistan
[2] Quaid I Azam Univ 45320, Dept Math, Islamabad 44000, Pakistan
[3] King Abdulaziz Univ 80203, Fac Sci, Dept Math, Nonlinear Anal & Appl Math NAAM Res Grp, Jeddah 21589, Saudi Arabia
[4] CIIT Ctr Hlth Res, Dept Math, Chak Shahzad Pk Rd, Islamabad, Pakistan