Não informado. (1929). Butler University botanical studies. Butler University, Department of Botany.
Chicago-viite (17. p.)Não informado. Butler University Botanical Studies. Indianapolis, Ind: Butler University, Department of Botany, 1929.
MLA-viite (8. p.)Não informado. Butler University Botanical Studies. Butler University, Department of Botany, 1929.
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