SKRYPNIK, W. I. Long-range order in quantum lattice systems of linear oscillators. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 58, n. 10, p. 1407–1424, 2006. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3542. Acesso em: 5 dec. 2025.