Não informado. (1971). Concrete abstracts. American Concrete Institute.
Chicago (17e ed.) BronvermeldingNão informado. Concrete Abstracts. Detroit, Mich: American Concrete Institute, 1971.
MLA (8e ed.) BronvermeldingNão informado. Concrete Abstracts. American Concrete Institute, 1971.
Let op: Deze citaties zijn niet altijd 100% accuraat.