RT Journal Article SR Electronic T1 Rapidly increasing promotional expenditures for e-cigarettes JF Tobacco Control JO Tob Control FD BMJ Publishing Group Ltd SP 110 OP 111 DO 10.1136/tobaccocontrol-2014-051580 VO 24 IS 2 A1 Rachel Kornfield A1 Jidong Huang A1 Lisa Vera A1 Sherry L Emery YR 2015 UL http://tobaccocontrol.bmj.com/content/24/2/110.abstract AB