WHO FCTC. Reporting on the implementation of the convention. Reporting on the implementation of the convention. http://www.who.int/fctc/reporting/en/ (accessed 2015-9-2)
WHO Tobacco Free Initiative. WHO report on the global tobacco epidemic, 2015. http://www.who.int/tobacco/global_report/2015/en/ (accessed 2015-9-2)
U.S. Department of Health and Human services. The health consequences of involuntary smoking. a report of the Surgeon General, 1986. http://profiles.nlm.nih.gov/ps/access/NNBCPM.pdf (accessed 2015-9-2)