1. Department of Studies in Mathematics, Davangere University, Shivagangotri, Davangere, India
2. Department of Mathematics, Davangere University, Shivagangotri, Davangere, India
3. Department of Physics, College of Science, King Faisal University, P. O. Box 400, Al-Ahsa 31982, Saudi Arabia
4. Laboratory of Fluid Mechanics, Department of Physics, Faculty of Sciences of Tunis, University of Tunis El Manar, 2092 Tunis, Tunisia