A.M. Mohagir, R. Kamga, C. Kapseu and C.F. Abi
Asian Journal of Applied Sciences 2 ( 4 ): 372 - 384 , 2009
G.P. Kofa, S. Ndi Koungou, G.J. Kayem and R. Kamga
Journal of Engineering and Applied Sciences 8 ( 4 ): 97 - 103 , 2013