World Health Organization. (1996). Cancer pain relief: With a guide to opioid availability. Geneva: World Health Organization.
Chicago-tyylinen lähdeviittausWorld Health Organization. Cancer Pain Relief: With a Guide to Opioid Availability. Geneva: World Health Organization, 1996.
MLA-viiteWorld Health Organization. Cancer Pain Relief: With a Guide to Opioid Availability. Geneva: World Health Organization, 1996.
Varoitus: Nämä viitteet eivät aina ole täysin luotettavia.