M.E. Toriman, A.C. Er, Mazlin Mokhtar, Rahmah Elfithri, Muhammad Barzani Gasim, Othman Karim, Mokhtar Jaafar, Nor Azlina Abdul Aziz and Nor Rohaizah Jamil
Journal of Engineering and Applied Sciences 6 ( 6 ): 423 - 427 , 2011