1. I. Ahmad:
Department of Mathematics, University of Malakand, Chakdara, DirLower, Pakistan
2. R. Naz:
Department of Mathematics, University of Malakand, Chakdara, Dir Lower, Pakistan
3. M. Rashad:
Department of Mathematics, University of Malakand, Chakdara, Dir Lower, Pakistan
4. A. Khan:
Department of Computer Science, University of Malakand, Chakdara, Pakistan