title: Is marijuana use becoming a 'gateway' to nicotine dependence?
authors.forename: Gary L
authors.initials: GL
authors.lastname: Humfleet
authors.forename: Amie L
authors.initials: AL
authors.lastname: Haas
mesh_terms: D000293:Adolescent; D000294:Adolescent Behavior; D006801:Humans; D008385:Marijuana Smoking / Q000523:psychology*; D012907:Smoking / Q000523:psychology; D014029:Tobacco Use Disorder / Q000209:etiology*