8[10]WCED.Our Common Future[M].Oxford:Oxford University Press,1987:8.
9[11]Cans H J.The Urban Villagers:Group and Class in the Life of Italian-Americans[M].New York:Free Press of Glencoe,1962:53.
10Young, K., Internet addiction: The emergence of a new clinical disorder. Retrieved February 13, 2001 from the World Wide Web: K. Young. Intemet addiction: The emergence of a new clinical disorder. http: //www.pitt.edu/- ksy/apa.html.