Flora of New York/Anthemideae, Inuleae, Helenieae

Tribe Anthemideae
The Asteraceae tribe ...

Achillea

 * http://www.biomedcentral.com/1471-2148/12/2
 * http://onlinelibrary.wiley.com/doi/10.1111/j.1558-5646.2007.00264.x/abstract