Dyfyniad APA
Davey, S. (2002). State of the world's vaccines and immunization. World Health Organization.
Dyfyniad Arddull Chicago
Davey, Sheila. State of the World's Vaccines and Immunization. Geneva: World Health Organization, 2002.
Dyfyniad MLA
Davey, Sheila. State of the World's Vaccines and Immunization. World Health Organization, 2002.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.