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http://www.google.com.sg/search?q=cache:JwFfXtopj0gJ:kitkat.wvu.edu:8080/files/3645.2.Casanova_Ana_dissertation.pdf+popularity+computer+mediated+communication++various+OR+forms+OR+many+OR+types+site:.edu+filetype:pdf&hl=en&lr=lang_en
: Analysis of CMC technologies as tools to enhance learning.

http://www.google.com.sg/search?q=cache:xMS7paP6vMsJ:www.american.edu/tesol/wpsquires.pdf+popularity+computer+mediated+communication++various+OR+forms+OR+many+OR+types+site:.edu+filetype:pdf&hl=en&lr=lang_en:
In particular, about the popularity of IM among American teenagers.