1. J.J. de Gier, Road traffic and illicit drugs, review of investigation of prevalence of illicit drugs in road traffic in different European countries, co-operation group to combat drug abuse and illicit trafficking in drugs (Pompidou group), ISBN-90-804577-1-X, 1998.
2. Drug and alcohol among suspected impaired drivers in Canton de Vaud (Switzerland);Augsburger;Forensic Sci. Int.,1997
3. Drugged driving, a review based on the experience in Norway;Christophersen;Drug Alcohol Depend.,1997
4. Role of drugs and alcohol in impaired drivers and fatally injured drivers in the Strathclyde police region of Scotland, 1995–1998;Seymore;Forensic Sci. Int.,1999
5. Driving under the influence of non-alcohol drugs;Mørland;Forensic Sci. Rev.,2000