[1] Chandigarh Univ, Univ Inst Sci, Dept Math, Mohali, Punjab, India
[2] King Saud Univ, Dept Basic Sci, Common Year 1, Riyadh 11451, Saudi Arabia
[3] King Saud Univ, Coll Sci, Dept Math, Riyadh 11451, Saudi Arabia
[4] Punjab Engn Coll, Dept Civil Engn, Chandigarh, India
[5] Zagazig Univ, Fac Sci, Dept Math, Zagazig, Egypt