Lüschen, Iris, Barbara Moschner, and Catherine Walter-Laager. 2017. “Interest + Engagement = Learning Growth? A Quantitative-Empirical Study on the Use of a Language Learning App by Young Children”. MediaEducation: Journal for Theory and Practice of Media Education 13 (Jahrbuch Medienpädagogik): 165-78. https://www.medienpaed.com/article/view/1017.