1. Department of Mathematics, University of Malakand, Chakdara Dir (L), 18000 Khyber Pakhtunkhwa, Pakistan
2. Art and Science Faculty, Department of Mathematics, Siirt University, TR-56100 Siirt, Turkey
3. Department of Mathematics and General Sciences, Prince Sultan University, P. O. Box 66833, Riyadh 11586, Saudi Arabia
4. Department of Medical Research, China Medical University, 40402 Taichung, Taiwan
5. Department of Computer Science and Information Engineering, Asia University, Taichung, Taiwan