Dyfyniad APA
World Health Organization & ebrary, Inc. (2007). Prevention. World Health Organization.
Dyfyniad Arddull Chicago
World Health Organization and Inc ebrary. Prevention. Geneva, Switzerland: World Health Organization, 2007.
Dyfyniad MLA
World Health Organization and Inc ebrary. Prevention. World Health Organization, 2007.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.