Não informado. World population year bulletin. World Federation of United Nations Associations.
Chicago (17e ed.) BronvermeldingNão informado. World Population Year Bulletin. Geneva, Suíça: World Federation of United Nations Associations.
MLA (8e ed.) BronvermeldingNão informado. World Population Year Bulletin. World Federation of United Nations Associations.
Let op: Deze citaties zijn niet altijd 100% accuraat.