Mendes, R. 2014. Função de Polya e a fórmula de Molien - DOI 10.5752/P.2316-9451.2014v2n2p92. Abakós. 2, 2 (May 2014), 92–99. DOI:https://doi.org/10.5752/P.2316-9451.2014v2n2p92.