Affiliation: | 1.Center for Development Research (ZEF), University of Bonn, Walter-Flex-Str. 3, 53113 Bonn, Germany ;2.Empresa Brasileira de Pesquisa Agropecuaria (EMBRAPA) Amaz^onia Oriental, Belém, Brazil ;3.Institute for Agricultural Engineering, University of G?ttingen, Germany ; |