KLOVE, Torleiv. A class of symmetric 2-bases. MATHEMATICA SCANDINAVICA, [S. l.], v. 47, p. 177–180, 1980. DOI: 10.7146/math.scand.a-11883. Disponível em: https://tidsskrift.dk/math/article/view/11883. Acesso em: 14 aug. 2026.