1. Center for Behavioral Health Statistics and Quality. The DAWN report: highlights of the 2011 Drug Abuse Warning Network (DAWN) findings on drug-related emergency department visits,2013
2. World Drug Report 2012,2012
3. Atlas on substance use (2010): resources for the prevention and treatment of substance use disorders,2010
4. United Nations (UN), Department of Economic and Social Affairs, Population Division. World population prospects: the 2010 revision. http://esa.unorg/unpd/wpp.
5. World Drug Report 2011,2011