Não informado. (1948). International Yearbook of Education. Unesco.
Chicago (17e ed.) BronvermeldingNão informado. International Yearbook of Education. Geneva, Suíça: Unesco, 1948.
MLA (8e ed.) BronvermeldingNão informado. International Yearbook of Education. Unesco, 1948.
Let op: Deze citaties zijn niet altijd 100% accuraat.