1. Adams, E., & Freeman, C. (2003). Selecting tools for online communities: Suggestions for learning technologists. The Technology Source. Available online at http://ts.mivu.org/default.asp?show+article&id=994 .
2. Berg, G. A. (2001). Distance learning best practices debate. WebNet Journal, 5–7.
3. Berge, Z., & Muilenburg, L. (2000). Barriers to distance education as perceived by managers and administrators: Results of a survey. In M. Clay (Ed.), Distance learning administration annual 2000. Baltimore, MD: University of Maryland.
4. Campbell, D., & Stanley, J. (1963). Experimental and quasi-experimental designs for research. Boston, MA: Houghton Mifflin.
5. Chen, B. (2009). Barriers to adoption of technology-mediated distance education in higher-education institutions. Quarterly Review of Distance Education, 10(4), 333–338.