Tittonell, P., Scopel, E., van Halsema, G.E., Andrieu, N., Posthumus, H., Mapfumo, P., Lahmar, R., Corbeels, M., Apina, T., Rakotoarisoa, J., Mtambanengwe, F., Pound, B., Chikowo, R. and Mkomwa, S. (2011) Agroecology-based aggradation-conservation agriculture (ABACO): targeting resource-limited and degraded environments of semi-arid Africa. In: Resilient Food Systems for a Changing World. 5th World Congress Conservation Agriculture and 3rd Farming Systems Design Conference, 26-29 September 2011, Brisbane, Australia. (Unpublished)