1. Amelink, C., Scales, G., & Tront, J. (2012). Student use of the tablet PC: Impact on student learning behaviors. Advances in Engineering Education, 3(1), 1–17.
2. Basoglu, E., & Akdemir, O. (2010). A comparison of undergraduate students’ English vocabulary learning: Using mobile phones and flash cards. The Turkish Online Journal of Educational Technology, 9(3), 1–7.
3. Burgess, S., & Murray, A. (2014). Use of traditional and smartphone app flashcards in an introductory psychology class. Journal of Instructional Pedagogies, 13, 1–7.
4. Chen, B., Seilhamer, R., Bennett, L., & Bauer, S. (2014). Students’ mobile learning practices in higher education: A multi-year study. Educause Review. Retrieved from: http://er.educause.edu/articles/2015/6/students-mobile-learning-practices-in-higher-education-a-multiyear-study . Accessed 1 July 2016.
5. Chien, C. (2015). Analysis the effectiveness of three online vocabulary flashcard websites on L2 learners’ level of lexical knowledge. English Language Teaching, 8(5), 111–121. https://doi.org/10.5539/elt.v8n5p111 .