8Nikaido T, Koike K, Mitsunaga K, et al. Two new triterpenoid saponins from platycodon grandiflorum [J]. Chem Pharm Bull, 1999, 47(6):903 - 904.
9He ZD, Qiao CF, Han QB, et al. New triterpenoid saponins from the roots of platycodon grandiflorum [J]. Tetrahedron, 2005, 61,2211 -2215.
10Kubota T, Kitatani H, Hinoh H. Structure of platycogenic acids A, B and C, further triterpenoid constituents of platycodon grandiflorum [J].J Chem Soc D, 1969, 22:1313 - 1314.
