This research was made while I was in Brazil, first as USAID-Vanderbilt visiting professor of economics at Instituto de Pesquisas Econômicas (IPE), University of São Paulo (1966-1968), then (overlapping) as economic advisor to Comissão Interestadual da Bacia Paraná-Uruguai (better known by its short name "Bacia") (1968-69). In the development of this study, I received help from several agencies and individuals.7 p.