1. http://www.unodc.org/pdf/research/wdr07/WDR_2007.pdf.
2. BBC Online Network, 4 October 1999 (http://news.bbc.co.uk/2/hi/uk_news/464200.stm).
3. BBC News, 25 June 2003 (http://news.bbc.co.uk/2/hi/europe/3021194.stm).
4. BBC News, 10 January 2007 (http://news.bbc.co.uk/2/hi/europe/6250189.stm).
5. Peer Reviewed: Drugs on Money.