Copyright The Authors 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco.
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Except where otherwise noted, this item's license is described as Copyright The Authors 2015. Published by Oxford University Press on behalf of the Society for Research on Nicotine and Tobacco. This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (<a href="http://creativecommons.org/licenses/by-nc/4.0/">http://creativecommons.org/licenses/by-nc/4.0/</a>), which permits non-commercial re-use, distribution, and reproduction in any medium, provided the original work is properly cited. For commercial re-use, please contact journals.permissions@oup.com