[Nazeer, Mubbashar] Univ Faisalabad, Govt Coll, Inst Arts & Sci, Dept Math, Chiniot Campus, Faisalabad 35400, Pakistan.
[Hussain, Farooq] Dept Math Sci FABS BUITEMS, Quetta 87300, Pakistan.
[Ahmad, M. Ozair; Saeed, Sadia] Univ Lahore, Dept Math, Lahore 54890, Pakistan.
[Khan, M. Ijaz] Riphah Int Univ I 14, Dept Mathemat & Stat, Islamabad 44000, Pakistan.
[Kadry, Seifedine] Beirut Arab Univ, Dept Math & Comp Sci, Beirut, Lebanon.