1. Institute of Mathematics, Khawaja Fareed University of Engineering & Information Technology, Abu Dhabi Road, 64200 Rahim Yar Khan, Punjab, Pakistan
2. Department of Mathematics, Science Faculty, Firat University, 23119 Elazig, Turkey
3. Department of Medical Research, China Medical University, Taichung, Taiwan
4. Faculty of Education, Yuzuncu Yil University, Van, Turkey
5. Department of Physics, Faculty of Science, The University of Maroua, P.O Box 814, Maroua, Cameroon