YUDITSKII, P. Analytic perturbation preserves determinacy of infinite index. MATHEMATICA SCANDINAVICA, [S. l.], v. 86, n. 2, p. 288–292, 2000. DOI: 10.7146/math.scand.a-14294. Disponível em: https://www.mscand.dk/article/view/14294. Acesso em: 5 may. 2024.