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?Ill. Handb. Laubholzk. 2: 73, 1907?. Submitted.

?Bull. New York Bot. Gard. 6: 394, 1910?. Submitted.

?Bull. Torrey Bot. Club 21: 17, pl.171, 1864?. Submitted.

?N. Amer. Fl. 24: 33, 1919?. Submitted.

?Amer. J. Sci. Arts 25: 74, 1834?. Submitted.

?Dendrol. Brit.  pl. 139, 1825?. Submitted.

?N. Amer. Fl. 24: 30, 1919?. Submitted.

?Flora 21: 750, 1838?. Submitted.

?Sp. Pl.  713, 1753?. Submitted.