1. Bright, M.: BT puts block on child porn sites. Observer (June 6, 2004), http://observer.guardian.co.uk/uk_news/story/0,6903,1232422,00.html
2. Brightview Internet Services Ltd.: WebMinder, a configuration for restricting access to obscene sites identified by the Internet Watch Foundation, 21 p. (June 9, 2005)
3. Dornseif, M.: Government mandated blocking of foreign Web content. In: von Knop, J., Haverkamp, W., Jessen, E. (eds.): Security, E-Learning, E-Services: Proceedings of the 17. DFN-Arbeitstagung über Kommunikationsnetze, Düsseldorf 2003, Lecture Notes in Informatics, pp. 617–648 (2003) ISSN 1617-5468
4. Edelman, B.: Web Sites Sharing IP Addresses: Prevalence and Significance. Berkman Center for Internet and Society at Harvard Law School (February 2003), http://cyber.law.harvard.edu/people/edelman/ip-sharing/
5. Her Majesty’s Stationery Office: Protection of Children Act (1978)