PT - JOURNAL ARTICLE AU - Scott T. Leatherdale AU - Rashid Ahmed AU - Murray Kaiserman TI - Marijuana use by tobacco smokers and nonsmokers: Who is smoking what? AID - 10.1503/cmaj.051614 DP - 2006 May 09 TA - Canadian Medical Association Journal PG - 1399--1399 VI - 174 IP - 10 4099 - http://www.cmaj.ca/content/174/10/1399.short 4100 - http://www.cmaj.ca/content/174/10/1399.full SO - CMAJ2006 May 09; 174