2Gunawardena Lowe & Anderson (1997). Analysis of a global online debate and the development of an interaction analysis model for examining social construction of knowledge in computer conferencing. Journal of Educational Computing Research. 17(4):397-431.
3Maarten D L.(2002).Network and content analysis in an online community discourse. Available: http://newmedia.colorado.edu/csel/62.html.
4Moore M G & Kearsley G. ([996). Distance Education:A system View Behnont: Wadsworth Publishing Company.
