Klerks, P. (1993). The state of Europe: A digest of European police systems, prison conditions, private security, human rights and civil liberties and the internal security situation in the 1990s. Domestic Security Research Foundation.
Chicago-Zitierstil (17. Ausg.)Klerks, Peter. The State of Europe: A Digest of European Police Systems, Prison Conditions, Private Security, Human Rights and Civil Liberties and the Internal Security Situation in the 1990s. Amsterdam: Domestic Security Research Foundation, 1993.
MLA-Zitierstil (8. Ausg.)Klerks, Peter. The State of Europe: A Digest of European Police Systems, Prison Conditions, Private Security, Human Rights and Civil Liberties and the Internal Security Situation in the 1990s. Domestic Security Research Foundation, 1993.