A pterocarpan from Erythrina orientalis. Hitoshi Tanaka, Toshihiro Tanaka and Hideo Etoh, Phytochemistry, Volume 45, Issue 1, May 1997, Pages 205-207, doi:10.1016/S0031-9422(96)00841-2
Two pterocarpans from Erythrina orientalis. Hitoshi Tanaka, Toshihiro Tanaka and Hideo Etoh, Phytochemistry, Volume 47, Issue 3, February 1998, pp. 475-477, doi:10.1016/S0031-9422(97)00596-7