TÁTRAI, Ferencz; MIHÁLYI, Kriszta. Open Badges in Education and Training in Europe. Opus et Educatio, [S. l.], v. 5, n. 4, 2018. 10.3311/ope.284. Disponível em: https://journals.bme.hu/oee/article/view/39066. Acesso em: 5 jul. 2025.