1. Allen, I. E., & Seaman, J. (2006). Making the grade: Online education in the United States, 2006. Needham, MA: Sloan Consortium.
2. Ball, A. F. (1995). Community-based learning in urban settings as a model for educational reform. Applied Behavioral Science Review, 3(2), 127–146.
3. Barron, B. (2006). Interest and self-sustained learning as catalysts of development: A learning ecology perspective. Human Development, 49(4), 193–224.
4. Baylor, A. (2004). Permutations of control: Cognitive considerations for agent-based learning environments. Journal of Interactive Learning Research, 15(4), 403–425.
5. Berg, S. L. (2003). Two sides of the same coin: Engaging students beyond the traditional classroom. Community College Enterprise, 9(1), 17–20.