Niu, D.-Y., Li, Y.-K., Wu, X.-X., Shi, Y.-D., Hu, Q.-F., & Gao, X.-M. (2013). Pterocarpan Derivatives from Clinopodium urticifolium and Their Cytotoxicity. Asian Journal of Chemistry, 25(17), 9672–9674. https://doi.org/10.14233/ajchem.2013.15127