1. Smoking Facts: What’s in a Cigarette? http://www.lung.org/stop-smoking/smoking-facts/whats-in-a-cigarette.html (Accessed 3 February 2016).
2. "Harmful and Potentially Harmful Constituents in Tobacco Products and Tobacco Smoke; Established List," 77 Federal Register 64 (3 April 2012), pp 20034 - 20037.
3. Quantitative determination of nitrobenzenes in cigarette smoke;Hoffmann;Anal. Chem.,1970
4. Chemical Components of Tobacco and Tobacco Smoke;Rodgman,2009
5. The less harmful cigarette: a controversial issue. a tribute to Ernst L. Wynder;Hoffmann;Chem. Res. Toxicol.,2001