World Health Organization. (1996). Cancer pain relief: With a guide to opioid availability (2nd ed.). WHO.
Chicago Style aipamenaWorld Health Organization. Cancer Pain Relief: With a Guide to Opioid Availability. 2nd ed. Geneva: WHO, 1996.
MLA aipamenaWorld Health Organization. Cancer Pain Relief: With a Guide to Opioid Availability. 2nd ed. WHO, 1996.
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