Não informado. (1914). Contributions from the Department of Botany. Pennsylvania State College, Department of Botany.
Chicago-viite (17. p.)Não informado. Contributions from the Department of Botany. State College, Pa: Pennsylvania State College, Department of Botany, 1914.
MLA-viite (8. p.)Não informado. Contributions from the Department of Botany. Pennsylvania State College, Department of Botany, 1914.
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