JAMES, Scott; SWAN, Karen; DASTON, Cassandra. Retention, Progression and the Taking of Online Courses. Online Learning, Boston, MA, v. 20, n. 2, 2015. DOI: 10.24059/olj.v20i2.780. Disponível em: https://olj.onlinelearningconsortium.org/index.php/olj/article/view/780. Acesso em: 1 apr. 2026.