Não informado. (1891). Contributions from the Gray Herbarium of Harvard University. Harvard University.
Chicago-viite (17. p.)Não informado. Contributions from the Gray Herbarium of Harvard University. Cambridge, Mass: Harvard University, 1891.
MLA-viite (8. p.)Não informado. Contributions from the Gray Herbarium of Harvard University. Harvard University, 1891.
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