Percentage Distribution of 6- to 12-year-olds, 1972-97. US Department of Education.
Čikaški stil citiranja (17. izdanje)Percentage Distribution of 6- to 12-year-olds, 1972-97. US Department of Education.
MLA način citiranja (9. izdanje)Percentage Distribution of 6- to 12-year-olds, 1972-97. US Department of Education.
Upozorenje: Ovi citati možda nisu uvijek 100% točni.