1. Agrawal A, Budney AJ, Lynskey MT: The co-occurring use and misuse of cannabis and tobacco: a review. Addiction. 2012, 107: 1221-1233. 10.1111/j.1360-0443.2012.03837.x.
2. Bélanger RE, Akre C, Kuntsche E, Gmel G, Suris J-C: Adding tobacco to cannabis–its frequency and likely implications. Nicotine Tob Res. 2011, 13: 746-750. 10.1093/ntr/ntr043.
3. Richter KP, Kaur H, Resnicow K, Nazir N, Mosier MC, Ahluwalia JS: Cigarette smoking among marijuana users in the United States. Subst Abus. 2005, 25: 35-43.
4. Detailed data Table 6.9B - Types of illicit drug use in the past month among persons aged 18 to 25, by past month cigarettes use: percentages. 2010,
http://www.samhsa.gov/data/NSDUH/2011SummNatFindDetTables/NSDUH-DetTabsPDFWHTML2011/2k11DetailedTabs/Web/HTML/NSDUH-DetTabsSect6peTabs1to54-2011.htm
, and 2011,
5. Radtke T, Keller R, Krebs H, Hornung R: Der Tabakkonsum Jugendlicher und junger Erwachsener in den Jahren 2001 bis 2009/10. Tabakmonitoring – Schweizerische Umfrage zum Tabakkonsum. [The tobacco consumption of young people in Switzerland between 2001 and 2009/10. Tobacco monitoring Switzerland - Swiss survey of tobacco consumption.]. 2001, Zurich: Psychologisches Institut der Universität Zürich, Sozial- und Gesundheitspsychologie, Retrieved from
http://www.tabakmonitoring.ch/Berichte/Jugendliche/Forschungsbericht/Gesamt_jugend_10_dt.pdf
, bis 2009/10. Tabakmonitoring – Schweizerische Umfrage zum Tabakkonsum. [The tobacco consumption of young people in Switzerland between 2001 and 2009/10. Tobacco monitoring Switzerland - Swiss survey of tobacco consumption.]