1. Allen, I. E., & Seaman, J. (2014). Grade change: Tracking online education in the United States. Babson Survey Research Group and Quahog Research Group. Retrieved from: http://www.onlinelearningsurvey.com/reports/gradechange.pdf .
2. Bank, B. J., Slavings, R. L., & Biddle, B. J. (1990). Effects of peer, faculty, and parental influences on students’ persistence. Sociology of Education, 63(3), 208. doi: 10.2307/2112838 .
3. Barnard, L., Lan, W. Y., To, Y. M., Paton, V. O., & Lai, S.-L. (2009). Measuring self-regulation in online and blended learning environments. The Internet and Higher Education, 12(1), 1–6. doi: 10.1016/j.iheduc.2008.10.005 .
4. Cho, M.-H., & Summers, J. (2012). Factor validity of the Motivated Strategies for Learning Questionnaire (MSLQ) in asynchronous online learning environments (AOLE). Journal of Interactive Learning Research, 32(1), 5–28.
5. Chung, L.-Y. (2015). Exploring the effectiveness of self-regulated learning in Massive Open Online Courses on non-native english speakers. International Journal of Distance Education Technologies, 13(3), 61–73. doi: 10.4018/IJDET.2015070105 .