PRESLEY, Regina G.; CUMBERLAND, Denise M.; ROSE, Kevin. A Comparison of Cognitive and Social Presence in Online Graduate Courses: Asynchronous vs. Synchronous Modalities. Online Learning, Boston, MA, v. 27, n. 2, 2023. DOI: 10.24059/olj.v27i2.3046. Disponível em: https://olj.onlinelearningconsortium.org/index.php/olj/article/view/3046. Acesso em: 26 mar. 2026.