LUCHA, Sylwia. A flat-rate income tax on revenue recorded as an effective form of taxation on the economic activities of individuals. SPC Journal of Education, [S. l.], v. 3, n. 1, p. 63–66, 2020. DOI: 10.14419/je.v3i1.30771. Disponível em: https://sciencepubco.com/index.php/JE/article/view/30771.. Acesso em: 2 may. 2024.