ГУРЕВИЧ, Д.А. У.М.Н.И.К. Perm Federal Research Centre Journal, [S. l.], n. 2, p. 88–90, 2012. Disponível em: https://journal-dev.icmm.ru/index.php/pscj/article/view/PSCJ2011n2p10. Acesso em: 5 may. 2026.