1. Department of Mathematics, Cankaya University, 06530 Balgat, Ankara, Turkey
2. Institute of Space sciences, Magyrele-Bucharest, Romania
3. Department of Medical Research, China Medical University Hospital, China Medical, University, Taichung, Taiwan
4. Department of Mathematics with Computer Applications, PSG College of Arts and Science, Coimbatore 641 046, India
5. Department of Mathematics, PSG College of Arts and Science, Coimbatore 641 046, India