F.  Kuginuki and Namba, T., ?Pharmacognostical studies on the folk medicine in Japan: 10. On "Otogiri-so". Anatomical features of leaves and stems of  Hypericum and Triadenum (Hypericaceae): 1.?, J. Jap. Bot., vol. 68, pp. 224-235 (1993) - illus., 1993.