YAKOVYV, I. Relationship of information and signs. Information Technology and Security, [S. l.], v. 1, n. 1, p. 31–41, 2012. DOI: 10.20535/2411-1031.2012.1.1.52719. Disponível em: http://its.iszzi.kpi.ua/article/view/52719. Acesso em: 23 sep. 2021.