@ARTICLE {SANGINGA:1990b, title = {Influence of reference trees on N2-fixation estimates in Leucaena leucocephala and Acacia albicia using 15N_ labelling techniques}, author = {Sanginga, N. and Danso, S. K. A. * and Zapata, F. and Bowen, G. D. }, journal = {Biology and Fertility of Soils}, year = {1990}, volume = {9}, pages = {341--346}, }