RT Journal Article SR Electronic T1 'Open-System’ electronic cigarettes cannot be regulated effectively JF Tobacco Control JO Tob Control FD BMJ Publishing Group Ltd SP 234 OP 235 DO 10.1136/tobaccocontrol-2019-055499 VO 30 IS 2 A1 Thomas Eissenberg A1 Eric Soule A1 Alan Shihadeh A1 , YR 2021 UL http://tobaccocontrol.bmj.com/content/30/2/234.abstract AB