... Weikersheim, Germa-ny. ISBN 3- 8 23 6-1 22 6 -3 . Müller-Sämann, Karl M., Kotschi, Johannes. Sustaining Growth, Soil fertility management in tropical smallholdings. 1994. GTZ/ CTA. ISBN 3- 8 23 6-1 22 6 -3 . Scoones ... Terre et Vie/CTA. ISBN 0 -3 3 3- 4 459 5 -3 . Dupriez, H., de Leener, Ph. and Tindall, H.D. Ways of Water, Run-off, Irrigation and Drainage. 1992. Terre et Vie/CTA. ISBN: 0 -3 3 3- 5707 8-2 . Gichuru, M.P., ... 0- 30 9-0 426 9-0 . Budelman A., Defoer T. Managing soil fertility in the tropics. KIT , The Netherlands. ISBN: 9 0-6 83 2-1 2 8-5 . With CD-rom. Chleq, J. and Dupriez, H. Vanishing Land and water, Soil...