[1] Univ Lakki Marwat, Dept Math Sci, Lakki Marwat, Pakistan
[2] Abdul Wali Khan Univ, Dept Math, Mardan, Pakistan
[3] King Abdulaziz Univ, Dept Math, Jeddah, Saudi Arabia
[4] Al Ain Univ, Coll Engn, Al Ain, U Arab Emirates
[5] Tafila Tech Univ, Dept Math, Tafila, Jordan