Rehder, Alfred (July 1921). "New Species, Varieties and Combinations from the Herbarium and the Collections of the Arnold Arboretum (continued)". Journal of the Arnold Arboretum. 3 (1): 11–51. doi:10.5962/p.317960. JSTOR43782540. S2CID240311504.
Rehder, Alfred (July 1921). "New Species, Varieties and Combinations from the Herbarium and the Collections of the Arnold Arboretum (continued)". Journal of the Arnold Arboretum. 3 (1): 11–51. doi:10.5962/p.317960. JSTOR43782540. S2CID240311504.
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Rehder, Alfred (July 1921). "New Species, Varieties and Combinations from the Herbarium and the Collections of the Arnold Arboretum (continued)". Journal of the Arnold Arboretum. 3 (1): 11–51. doi:10.5962/p.317960. JSTOR43782540. S2CID240311504.