Buhringer, Gerhard and Farrell, Michael and Kraus, Ludwig and Marsden, John and Pfeiffer-Gerschel, Tim and Piontek, Daniela and Karachaliou, Krystallia and Kunzel, Jutta and Stillwell, Garry (2009) Comparative analysis of research into illicit drugs in the european union. Full report. Brussels: European Commission. Directorate General for Justice and Home Affairs. Drugs Coordination Unit.

Buhringer, Gerhard and Farrell, Michael and Kraus, Ludwig and Marsden, John and Pfeiffer-Gerschel, Tim and Piontek, Daniela and Karachaliou, Krystallia and Kunzel, Jutta and Stillwell, Garry (2009) Comparative analysis of research into illicit drugs in the european union. Executive summary. Brussels: European Commission. Directorate General for Justice and Home Affairs. Drugs Coordination Unit.