1. The Joint Commission Facts about pain management http://www.jointcommission.org/pain_management/
2. Pain management: a fundamental human right;Brennan;Anesthesia and Analgesia,2007
3. European Federation of IASP Chapters EFIC's declaration on chronic pain as a major healthcare problem, a disease in its own right Brussels, Belgium 2001 http://www.iasp-pain.org/AM/Template.cfm?Section=Press_Release&Template=/CM/ContentDisplay.cfm&ContentID=2915
4. World Health Organization World Health Organization supports global effort to relieve chronic pain, 2004 http://www.who.int/mediacentre/news/releases/2004/pr70/en/