All Rights Reserved
AccessEcon LLC 2006, 2008.
Powered by MinhViet JSC
ralph lauren polo

First Author:
Helton Saulo
Department of Economics - Federal University of Rio Grande do Sul / Porto Alegre, RS, Brazil
Porto Alegre, 90010-350, Brazil

Second Author:

Jeremias Leao
Department of Mathematics - Federal University of Piaui / Picos, PI, Brazil