8Sang T,Crawford D J,Stuessy T F.Documentation of reticulate evolution in peonies (Paeonia) using internal transcribed spacer sequences of nuclear ribosomal DNA:implication for biogeography and concerted evolution[J].Proc Natl Acad Sci USA,1995,92:6813-6817.
9Baldwin B G,Sanderson M J,Porter J M,et al.The ITS region of nuclear ribosomal DNA:a valuable source of evidence on angiosperm phylogeny[J].Ann Missouri Bot Gard,1995,82:247-277.
10Lee B Y,Downie S R.A molecular phylogeny of Apiaceae tribe Caucalideae and related taxa:inferences based on ITS sequence data[J].Syst Bot,1999,24:461-478.