DLOUHÁ, J. Úvodník 2021/XVI/1. Envigogika, Praha, Czech Republic, v. 16, n. 1, 2021. DOI: 10.14712/18023061.631. Disponível em: https://envigogika.czp.cuni.cz/index.php/Envigogika/article/view/631. Acesso em: 6 dec. 2021.