Rippel, R., V. C. Limberger Rippel, and M. T. Michelon. “Economically Active Population and Family Heads Immigrants in West of Paraná State - Impacts on Regional Development - An Analysis by Sectors of Economy”. Informe GEPEC, vol. 15, no. 3, Jan. 2000, pp. 107-2, doi:10.48075/igepec.v15i3.6274.