Simultaneous determination of 6 active components in Chrysanthemum morifolium by HPLC Chemical constituents from herbs of Erigeron breviscapus Quantitative analysis multi-components by single marker for simultaneous determination of six caffeoylquinic acids in Yinhuang Tablets Quantitative analysis on multi-components by single marker for simultaneousdetermination of six caffeoylquinic acids in Yinhuang Tablets