CHEN, Yang; BURTON, Terry; VORVOREANU, Mihaela; WHITTINGHILL, David M. Cogent: Case Study of Meaningful Gamification in Education with Virtual Currency. International Journal of Emerging Technologies in Learning (iJET), [S. l.], v. 10, n. 1, p. pp. 39–45, 2015. DOI: 10.3991/ijet.v10i1.4247. Disponível em: https://online-journals.org/index.php/i-jet/article/view/4247. Acesso em: 26 apr. 2024.