1. European Commission Europa Report http://ec.europa.eu/health/determinants/lifestyle/tobacco/tobacco_en.htm
2. European Commission, Survey on Tobacco Flash EB series 253 http://ec.europa.eu/health/ph_determinants/life_style/Tobacco/Documents/eb_253_en.pdf
3. Cigarette smoking among adults-United States, 2006;Rock;MMWR Weekly,2007
4. Falling prevalence of smoking: how low can we go?;Chapman;Tob Control,2007
5. Lancaster T Stead L Physician advice for smoking cessation Cochrane Database Syst Rev 2008