1. Alexander, P.A.: Psychology in Learning and Instruction. Pearson Prentice Hall, New Jersey (2006)
2. Allan, B.: Blended Learning Tools for Teaching and Training. Facet Publishing, London (2007)
3. Allen, I.E., Seaman, J., Garrett, R.: Blended. In: The Extent and Promise of Blended Education in the United States. Sloan-Consortium, Needham (2007)
4. Arbaugh, J.B.: An Empirical Verification of the Community of Inquiry Framework, Sloan Consortium. Journal of Asynchronous Learning Networks 11(1) (2007) (Retrieved January 20, 2008), http://www.sloan-c.org/publications/jaln/v11n1/v11n1_9arbaugh.asp
5. Blase, J., Blase, J.: Effective instructional leadership Teachers’ perspectives on how principals promote teaching and learning in schools. Journal of Educational Administration 38(2), 130–141 (2000)