RT Journal Article SR Electronic T1 Taxes, prices and illicit trade: the need for sound evidence JF Tobacco Control JO Tob Control FD BMJ Publishing Group Ltd SP e1 OP e2 DO 10.1136/tobaccocontrol-2014-051739 VO 23 IS e1 A1 Frank J Chaloupka YR 2014 UL http://tobaccocontrol.bmj.com/content/23/e1/e1.abstract AB