3March 2011, The State of the News Media-An Annual Report on American Journalism 2011, by Tom Rosenstiel and Amy Mitchell. http:// stateofthemedia.org/.
4White, David Manning. (1964). "The "Gatekeeper': A Case Study In the Selection of News, In: Lewis A. Dexter/David M. White (Hrsg,): People, Society and Mass Communications. London S. 160 - 172.