Não informado. (1939). Contributions from the University of Michigan Herbarium. University of Michigan Herbarium.
Chicago-viite (17. p.)Não informado. Contributions from the University of Michigan Herbarium. Ann Arbor, Mich: University of Michigan Herbarium, 1939.
MLA-viite (8. p.)Não informado. Contributions from the University of Michigan Herbarium. University of Michigan Herbarium, 1939.
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