Isomorphic Hamiltonian system which are not isomorphic as quantum systems. Neliniini Kolyvannya, [S. l.], v. 3, n. 1, p. 53–56, 2000. Disponível em: https://twinhead.imath.kiev.ua/index.php/nosc/article/view/96. Acesso em: 22 jan. 2026.