1. M. Jawed Iqbal:
1Institute of Space and Planetary Astrophysics, University of Karachi, Karachi, Pakistan; Department of Mathematics, University of Karachi, Karachi, Pakistan
2. Zaeemuddin Ali:
Institute of Space and Planetary Astrophysics, University of Karachi, Karachi, Pakistan
3. S. Shahid Ali:
Department of Geography, University of Karachi, Karachi, Pakistan