APA (7e ed.) Bronvermelding

Não informado. (1968). Research Results Digest. National Cooperative Highway Research Program.

Chicago (17e ed.) Bronvermelding

Não informado. Research Results Digest. Washington: National Cooperative Highway Research Program, 1968.

MLA (8e ed.) Bronvermelding

Não informado. Research Results Digest. National Cooperative Highway Research Program, 1968.

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