Baggio, Stéphanie, Joseph Studer, Meichun Mohler-Kuo, Jean-Bernard Daeppen, and Gerhard Gmel. 2013. “Profiles of Drug Users in Switzerland and Effects of early-Onset Intensive Use of Alcohol, Tobacco and cannabis on other Illicit Drug Use”. Swiss Medical Weekly 143 (2324):w13805. https://doi.org/10.4414/smw.2013.13805.