KISELEV, S. I.; KHMELENKO, V. V.; LEE, D. M. Sound propagation in liquid He in impurity-helium solids: Low-Temperature Physics and Chemistry in Cryomatrice. ФІЗИКА НИЗЬКИХ ТЕМПЕРАТУР, Харків, Україна, v. 26, n. 9-10, p. 874–883, 2000. DOI: 10.1063/1.1312389. Disponível em: https://fnt.ilt.kharkiv.ua/index.php/fnt/article/view/f26-0874e. Acesso em: 3 трав. 2024.