LUSHKIN, O. Y. On Efficient Thermionic Cathodes. Ukrainian Journal of Physics, [S. l.], v. 60, n. 1, p. 74, 2019. DOI: 10.15407/ujpe60.01.0074. Disponível em: https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2019289. Acesso em: 19 apr. 2024.