APA (7th ed.) Zitazioa
ebrary, Inc. (2005). International travel and health: Situation as on 1 January 2005. World Health Organization.
Chicago Style (17th ed.) Zitazioa
ebrary, Inc. International Travel and Health: Situation as on 1 January 2005. Geneva: World Health Organization, 2005.
MLA (9th ed.) Zitazioa
ebrary, Inc. International Travel and Health: Situation as on 1 January 2005. World Health Organization, 2005.
Kontuz: berrikusi erreferentzia hauek erabili aurretik.