SUWARDI, S. Maintaining Progresiveness of Personal Income Tax Rates in The Indonesian Income Tax Law. International Journal of Pertapsi, [S. l.], v. 1, n. 1, p. 41–50, 2023. DOI: 10.9744/ijp.1.1.41-50. Disponível em: https://ojs-pertapsi.petra.ac.id/index.php/pertapsi/article/view/11. Acesso em: 26 dec. 2025.