''‘Sed quis custodiet ipsos custodes.''

Who will watch the watchmen?

Schmid, G. (11 July 2001). "Report on the existence of a global system for the interception of private and commercial communications (ECHELON interception system) (2001/2098(INI))". Session document A5-0264/2001. European Parliament. Retrieved 21 December 2006.

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