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or report erroneous counts.
Semple, J. C., J. G. Chmielewski & M. E. Lane. 1989. Chromosome number determinations in fam. Compositae, tribe Astereae. III. Additional counts and comments on generic limits and ancestral base numbers. Rhodora 91: 296–314.
Semple, J. C., J. G. Chmielewski & C. Xiang. 1992. Chromosome number determinations in fam. Compositae, tribe Astereae. IV. Additional reports and comments on the cytogeography and status of some species of Aster and Solidago. Rhodora 94: 48–62.
Semple, J. C., C. Xiang, J. Zhang, M. Horsburgh & R. Cook. 2001. Chromosme number determinations in Fam. Compositae, tribe Astereae. VI. Western North American taxa and comments on generic treatments of North American asters. Rhodora 103: 202–218.