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Keyes, Katherine M., Melanie Wall, Magdalena Cerdá, John Schulenberg, Patrick M. O’Malley, Sandro Galea, Tianshu Feng, and Deborah S. Hasin. "How Does State Marijuana Policy Affect U.S. Youth? Medical Marijuana Laws, Marijuana Use and Perceived Harmfulness: 1991–2014." Addiction 2016.

Keyes, Katherine M., et al. "How Does State Marijuana Policy Affect U.S. Youth? Medical Marijuana Laws, Marijuana Use and Perceived Harmfulness: 1991–2014." Addiction 2016.