@BOOK {MULONGOY:1987, title = {Influence of biological processes on soil fertility: research priority for sustained crop production in the tropics.}, author = {Mulongoy, K. }, booktitle = {Colloques et Seminaires - Les Arbres Fixateur d'Azote L'Amelioration Biologique de la Fertilite du Sol}, year = {1987}, publisher = {Actes des Seminaires, ORSTOM}, address = {Darkar}, }