NWANYANWU, Loveday A.; OFIAFOH, Eiya. Assessing the Productivity of Personal Income Tax System in Nigeria. Account and Financial Management Journal, [S. l.], v. 1, n. 07, p. 439–448, 2016. Disponível em: http://everant.org/index.php/afmjh/article/view/220. Acesso em: 17 may. 2024.