REKTOR SIANTURI. INTERPRETASI KOMBINATORIAL BILANGAN EULER. Visipena, [S. l.], v. 6, n. 1, p. 102–110, 2015. DOI: 10.46244/visipena.v6i1.359. Disponível em: https://ejournal.bbg.ac.id/index.php/visipena/article/view/359. Acesso em: 3 aug. 2026.