1. Institute of Space and Planetary Astrophysics (ISPA), University of Karachi, Karachi 75270, Pakistan
2. Faculty of Engineering Sciences, National University of Science Technology, Islamabad 46000, Pakistan
3. Centre for Mathematical Plasma-Astrophysics, Department of Mathematics, KU Leuven, Celestijnenlaan 200B, B-3001 Heverlee, Belgium
4. Katholieke Universiteit Leuven Campus Kortrijk, E.-Sabbelaan 53, B-8500 Kortrijk, Belgium