1. U.S. Department of Health and Human Services. The health consequences of smoking—50 years of progress: a report of the Surgeon General, 2014.
2. International Agency for Research on Cancer;World Health Organization,2004
3. World Health Organization, (n.d.). 〈https://www.who.int/news-room/fact-sheets/detail/tobacco〉 (accessed February 22, 2021).
4. World Health Organization, (n.d.). 〈https://www.who.int/news/item/19–12-2019-who-launches-new-report-on-global-tobacco-use-trends〉 (accessed February 22, 2021).
5. Assessment of salivary cotinine concentration among general non-smokers population: before and after Spanish smoking legislations;Lidón-Moyano;Cancer Epidemiol.,2017