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Keller, Paula A., Eric J. Beyer, Timothy B. Baker, Linda A. Bailey, och Michael C. Fiore. Tobacco Cessation Quitline Spending in 2005 and 2006: What State-Level Factors Matter? Molecular Diversity Preservation International (MDPI), 2009.

Keller, Paula A., et al. Tobacco Cessation Quitline Spending in 2005 and 2006: What State-Level Factors Matter? Molecular Diversity Preservation International (MDPI), 2009.