@ARTICLE {SANGINGA:1989b, title = {Nitrogen fixation of field-inoculated Leucaena leucocephala (Lam.) de Wit estimated by the 15N and the difference methods}, author = {Sanginga, N. and Mulongoy, K. and Ayanaba, A. }, journal = {Plant and Soil}, year = {1989}, volume = {117}, pages = {269--274}, }