ZHOU, SIZHONG; PAN, QUANRU. An isolated toughness condition for graphs to be fractional (a, b, k)-critical graphs. Utilitas Mathematica , [S. l.], v. 92, 2013. Disponível em: https://utilitasmathematica.com/index.php/Index/article/view/937. Acesso em: 8 may. 2026.