KON, A. Service activities: reviewing concepts and typologies. Brazilian Journal of Political Economy, [S. l.], v. 19, n. 2, p. 307-328, 1999. DOI: 10.1590/0101-31571999-1024. Disponível em: https://centrodeeconomiapolitica.org/repojs/index.php/journal/article/view/1057. Acesso em: 4 may. 2024.