Khalifa, AlBara, Tsuneo Kato, and Seiichi Yamamoto. “Learning Effect of Implicit Learning in Joining-in-Type Robot-Assisted Language Learning System”. International Journal of Emerging Technologies in Learning (iJET) 14, no. 02 (January 30, 2019): pp. 105–123. Accessed August 15, 2022. https://online-journals.org/index.php/i-jet/article/view/9212.