Não informado. (1961). API Abstracts of Refining Patents. American Petroleum Institute.
Chicago (17e ed.) BronvermeldingNão informado. API Abstracts of Refining Patents. New York: American Petroleum Institute, 1961.
MLA (8e ed.) BronvermeldingNão informado. API Abstracts of Refining Patents. American Petroleum Institute, 1961.
Let op: Deze citaties zijn niet altijd 100% accuraat.