APA (7e ed.) Bronvermelding

Percentage Distribution of 6- to 12-year-olds, 1972-97. US Department of Education.

Chicago (17e ed.) Bronvermelding

Percentage Distribution of 6- to 12-year-olds, 1972-97. US Department of Education.

MLA (9e ed.) Bronvermelding

Percentage Distribution of 6- to 12-year-olds, 1972-97. US Department of Education.

Let op: Deze citaties zijn niet altijd 100% accuraat.