1. American Pain Society. Principles of Analgesic Use in the Treatment of Acute Pain and Cancer Pain, 5th edition. Glenview, IL: American Pain Society; 2003.
2. American Pain Society Recommendations for Improving the Quality of Acute and Cancer Pain Management
3. Miaskowski C Cleary J Burney R Guideline for the Management of Cancer Pain in Adults and Children. APS Clinical Practice Guidelines Series, No. 3. Glenview, IL: American Pain Society; 2005.
4. World Health Organization. Cancer Pain Relief: With a Guide to Opioid Availability, 2nd edition. Geneva, Switzerland: World Health Organization; 1996.
5. Opioids for chronic pain: Taking stock