M.S.A. Rahim, N.Z.M. Saat, H. Siti Aishah, S.A. Arshad, N.A.A. Aziz, N.N. Zakaria, K. Kaur, M.M. Kamaruddin and N.H.F. Suhaimi
Journal of Applied Sciences 16 ( 3 ): 108 - 112 , 2016
R. Kakar, K. Kaur and K.C. Gupta
Journal of Modern Mathematics and Statistics 7 ( 3 ): 26 - 31 , 2013