TY - JOUR T1 - Adolescent smoking JF - Canadian Medical Association Journal JO - CMAJ SP - 657 LP - 657 DO - 10.1503/cmaj.1060178 VL - 176 IS - 5 AU - Paul R. Preston Y1 - 2007/02/27 UR - http://www.cmaj.ca/content/176/5/657.1.abstract ER -