PANCHENKO, Sergey. Informal Activity in Modern Society. Gosudarstvennaya Sluzhba, [S. l.], v. 13, n. 2, p. 103–105, 2011. Disponível em: https://gosudarstvennaya-sluzhba.owebs.ru/article/view/21280. Acesso em: 9 nov. 2026.