Não informado. (1968). IBP boletim interamericano. U.S. National Academy of Sciences, International Biological Programe.
Chicago (17e ed.) BronvermeldingNão informado. IBP Boletim Interamericano. Washington: U.S. National Academy of Sciences, International Biological Programe, 1968.
MLA (8e ed.) BronvermeldingNão informado. IBP Boletim Interamericano. U.S. National Academy of Sciences, International Biological Programe, 1968.
Let op: Deze citaties zijn niet altijd 100% accuraat.