Source: Drug and Alcohol Dependence,
Date published: 25/04/2012

Source: European Psychiatric Association ,
Date published: 05/03/2012

Source: Addictive Behaviors,
Date published: 24/02/2012

Source: BioSpace ,
Date published: 22/12/2011

Source: UK Teratology Information Service,
Date published: 08/11/2011

Source: Medical Journal of Australia,
Date published: 03/10/2011

Source: UK Teratology Information Service,
Date published: 01/09/2011

Source: Cochrane Library,
Date published: 11/07/2011