1. EMCDDA, Europol EU drug markets report 2012 http://www.emcdda.europa.eu/attachements.cfm/att_194336_EN_TD3112366ENC.pdf
2. EMCDDA Annual Report on the State of the Drugs Problem in Europe 2011 http://www.emcdda.europa.eu/attachements.cfm/att_143743_EN_EMCDDA_AR2011_EN.pdf
3. EMCDDA Annual Report on the State of the Drugs Problem in Europe 2010 http://www.emcdda.europa.eu/attachements.cfm/att_120104_EN_EMCDDA_AR2010_EN.pdf
4. EMCDDA Annual Report on the State of the Drugs Problem in Europe 2009 http://www.emcdda.europa.eu/attachements.cfm/att_93236_EN_EMCDDA_AR2009_EN.pdf