Não informado. (1972). Ecological Research Series. U.S. Environmental Protection Agency.
Chicago (17e ed.) BronvermeldingNão informado. Ecological Research Series. Washington: U.S. Environmental Protection Agency, 1972.
MLA (8e ed.) BronvermeldingNão informado. Ecological Research Series. U.S. Environmental Protection Agency, 1972.
Let op: Deze citaties zijn niet altijd 100% accuraat.