APA (7e ed.) Bronvermelding

Não informado. (1973). Energy index. Environment Information Center, Energy Reference Department.

Chicago (17e ed.) Bronvermelding

Não informado. Energy Index. New York: Environment Information Center, Energy Reference Department, 1973.

MLA (8e ed.) Bronvermelding

Não informado. Energy Index. Environment Information Center, Energy Reference Department, 1973.

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