BOUZEFRANE, MOHAMED; CHELLALI, MUSTAPHA; HAYNES, TERESA W. Global defensive alliances in trees. Utilitas Mathematica , [S. l.], v. 82, 2010. Disponível em: https://utilitasmathematica.com/index.php/Index/article/view/694. Acesso em: 8 may. 2026.