1. In the following, certain references are listed, although they do not appear in the text, since they were important in the research done for this article. They are CNS (1992), ECOTEC (1993), FUNTAC (1991), Hecht/IEA/FUNTAC (1995), Redford and Padoch (1993), Kainer et al. (2003), Pacheo (1992) .
2. A journey in Brazil /