Saif- ur-Rehman, Iffat Batool and Gulgoona Younas
Journal of Applied Sciences 1 ( 1 ): 6 - 7 , 2001
Saif- ur-Rehman, Gulgoona Younas, Atif Riaz, M. Alamgir and Zaheer Ahmed
Journal of Applied Sciences 2 ( 6 ): 637 - 642 , 2002