APA (7e ed.) Bronvermelding

(1968). The 1968 World Book Year Book. Field Enterprises Educational Corporation.

Chicago (17e ed.) Bronvermelding

The 1968 World Book Year Book. Chicago, Estados Unidos: Field Enterprises Educational Corporation, 1968.

MLA (9e ed.) Bronvermelding

The 1968 World Book Year Book. Field Enterprises Educational Corporation, 1968.

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