1. Valiathan, P.: Blended Learning Models, 16 February 2016. www.learningcircuits.com/2002/aug2002/valiathan.html
2. Friesen, N.: Report: Defining blended learning, 18 February 2016. http://learningspaces.org/papers/Defining_Blended_Learning_NF.pdf
3. Clark, D.: Blended Learning: An EPIC White Paper, 18 February 2016. http://learningspaces.org/papers/Defining_Blended_Learning_NF.pdf
4. Bonk, C.J., Graham, C.R.: The Handbook of Blended Learning Environments: Global Perspectives, Local Designs. Jossey-Bass/Pfeiffer, San Francisco (2006)
5. Randy Garrison, D., Vaughan, N.D.: Blended Learning in Higher Education: Framework, Principles, and Guidelines. Jossey-Bass, Wiley online library (2007)