Isolation, Structural Elucidation, and Cytotoxicity of Three New ent-Kaurane Diterpenoids from Isodon japonica var. glaucocalyx - Liang, Hui-Juan; Zhang, Yun-Xiao; Hai, Guang-Fan; Bai, Su-Ping; Yuan, Yong-Liang; Ye, Dan-Dan; Zhou, Nan-Qian (Planta Medica, 2013)