Não informado. (2017). World Health Statistics. World Health Organization.
Chicago (17e ed.) BronvermeldingNão informado. World Health Statistics. Geneva, Suíça: World Health Organization, 2017.
MLA (8e ed.) BronvermeldingNão informado. World Health Statistics. World Health Organization, 2017.
Let op: Deze citaties zijn niet altijd 100% accuraat.