N.Z. Lupwayi, M.A. Arshad, R.H. Azooz and Y.K. Soon
Canadian journal of Soil Sciences 89 ( 2 ): 169 - 177 , 2009
S.S. Malhi, Y.K. Soon, C.A. Grant, R. Lemke and N. Lupwayi
Canadian journal of Soil Sciences 90 ( 2 ): 363 - 372 , 2010