FOG, D. Contingency tables and approximate $\chi^2$-distributions. MATHEMATICA SCANDINAVICA, [S. l.], v. 1, p. 93–103, 1953. DOI: 10.7146/math.scand.a-10368. Disponível em: https://www.mscand.dk/article/view/10368. Acesso em: 5 may. 2024.