World Health Organization. (2011). World health statistics 2011. World Health Organization.
Chicago (17e ed.) BronvermeldingWorld Health Organization. World Health Statistics 2011. Geneva, Switzerland: World Health Organization, 2011.
MLA (8e ed.) BronvermeldingWorld Health Organization. World Health Statistics 2011. World Health Organization, 2011.
Let op: Deze citaties zijn niet altijd 100% accuraat.