Bergamin, P. B., S. Ziska, E. Werlen, and E. Siegenthaler. “The Relationship Between Flexible and Self-Regulated Learning in Open and Distance Universities”. The International Review of Research in Open and Distributed Learning, Vol. 13, no. 2, Apr. 2012, pp. 101-23, doi:10.19173/irrodl.v13i2.1124.