APA (7e ed.) Bronvermelding

Não informado. (1999). Shools in the middle. National Association of Secondary School Principals.

Chicago (17e ed.) Bronvermelding

Não informado. Shools in the Middle. Reston, Va: National Association of Secondary School Principals, 1999.

MLA (8e ed.) Bronvermelding

Não informado. Shools in the Middle. National Association of Secondary School Principals, 1999.

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