1. S. Hussain:
Department of Mathematics, College of Science Al Zulfi, Majmaah University, Kingdom of Saudi Arabia
2. M. A. Kamal:
Department of Mathematics, Suleman Bin Abdul Aziz University, Al-Kharj, Kingdom of Saudi Arabia
3. F. Ahmad:
Department of Mathematics, College of Science Al Zulfi, Majmaah University, Kingdom of Saudi Arabia