1. Anhui International Studies University, Anhui, China
2. Abdus Salam School of Mathematical Sciences, Government College University, Lahore, Pakistan
3. Department of Mathematics, Government College University, Lahore, Pakistan
4. Department of Mathematics, COMSATS University Islamabad, Lahore Campus, Lahore, Pakistan
5. Faculty of Education, Van Yuzuncu Yil University, Van, Turkey