Não informado. (1891). Contributions fron the Department of Botany and Rocky Mountain Herbarium. University of Wyoming.
Chicago-viite (17. p.)Não informado. Contributions Fron the Department of Botany and Rocky Mountain Herbarium. Laramie, Wyo: University of Wyoming, 1891.
MLA-viite (8. p.)Não informado. Contributions Fron the Department of Botany and Rocky Mountain Herbarium. University of Wyoming, 1891.
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