Não informado. (1891). Contributions fron the Department of Botany and Rocky Mountain Herbarium. University of Wyoming.
Παραπομπή σε μορφή Chicago (17η εκδ.)Não informado. Contributions Fron the Department of Botany and Rocky Mountain Herbarium. Laramie, Wyo: University of Wyoming, 1891.
Παραπομπή σε μορφή MLA (8th εκδ.)Não informado. Contributions Fron the Department of Botany and Rocky Mountain Herbarium. University of Wyoming, 1891.
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