STEFANSSON, G.; LENTIN, J. From Smileys to Smileycoins: Using a Cryptocurrency in Education. Ledger, [S. l.], v. 2, p. 38–54, 2017. DOI: 10.5195/ledger.2017.103. Disponível em: https://ledger.pitt.edu/ojs/ledger/article/view/103. Acesso em: 20 jun. 2024.