1. 2Nua Internet Surveys, 2002 How Many Online? http://www.nua.com/surveys/how_many_online/index.html.
2. 3H. Taylor, 2001, The most frequent uses of the Internet are e-mail, news, information seeking and research . The Harris PollR,11http://www.harrisinteractive.com/harris_poll/index.asp?PID=221.
3. 4National Library of Medicine.medlineplus visitor profile survey results. 2001 http://www.nlm.nih.gov/medlineplus/survey/msurveyresults.html.