HANANI, H. A Note on Steiner Triple Systems. MATHEMATICA SCANDINAVICA, [S. l.], v. 8, p. 154–156, 1960. DOI: 10.7146/math.scand.a-10603. Disponível em: https://www.mscand.dk/article/view/10603. Acesso em: 4 may. 2024.