1. M. J. Iqbal:
Department of Mathematics, University of Engineering and Technology,Lahore,Pakistan
2. S. Rehman:
Department of Mathematics, University of Engineering and Technology,Lahore,Pakistan
3. A. Pervaiz:
Department of Mathematics, University of Engineering and Technology,Lahore,Pakistan
4. A. Hakeem:
Department of Mathematics, University of Engineering and Technology,Lahore,Pakistan