APA-viite (7. p.)
World Health Organization & ebrary, Inc. (2009). International travel and health: Situation as on 1 January 2009. World Health Organization.
Chicago-viite (17. p.)
World Health Organization ja Inc ebrary. International Travel and Health: Situation as on 1 January 2009. Geneva: World Health Organization, 2009.
MLA-viite (9. p.)
World Health Organization ja Inc ebrary. International Travel and Health: Situation as on 1 January 2009. World Health Organization, 2009.
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