Não informado. (1929). Butler University botanical studies. Butler University, Department of Botany.
Chicago (17e ed.) BronvermeldingNão informado. Butler University Botanical Studies. Indianapolis, Ind: Butler University, Department of Botany, 1929.
MLA (8e ed.) BronvermeldingNão informado. Butler University Botanical Studies. Butler University, Department of Botany, 1929.
Let op: Deze citaties zijn niet altijd 100% accuraat.