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Ferns of the national forests in Alaskafederal docPublished 2008
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by Weinstein, Mobee
Published 2019 -
Ferns of the northwestcovering Washington Oregon Idaho British Columbia Montana Wyoming central and northern CaliforniaBookby Frye, Theodore C. (Theodore Christian), 1869-1962
Published 1934 -
by Taylor, Thomas Mayne Cunninghame, 1904-1983
Published 1970