SHEA, Peter. Introduction to Online Learning, Volume 23, Issue 2. Online Learning, Boston, MA, v. 23, n. 2, 2019. DOI: 10.24059/olj.v23i2.2027. Disponível em: https://olj.onlinelearningconsortium.org/index.php/olj/article/view/2027. Acesso em: 25 mar. 2026.