ZHANG, Haiyan. A Flipped Classroom-Based Education System for College English Teaching. International Journal of Emerging Technologies in Learning (iJET), [S. l.], v. 14, n. 16, p. pp. 120–129, 2019. DOI: 10.3991/ijet.v14i16.11152. Disponível em: https://online-journals.org/index.php/i-jet/article/view/11152. Acesso em: 19 apr. 2024.