LECK, UWE; LECK, VOLKER. There is no ODC with all pages isomorphic to C4U̇C3U̇C3U̇ν. Utilitas Mathematica , [S. l.], v. 49, 1996. Disponível em: https://utilitasmathematica.com/index.php/Index/article/view/6. Acesso em: 8 may. 2026.