1. a) O. Tanaka, and R. Kasai, Saponins of ginseng and related plants, in: Fortschritte der Chemie Organischer Naturstoffe, Vol. 46, W. Hertz, H. Grisebach, G. W. Kirby, and Ch. Tatum, eds., Springer-Verlag, Wien, New York, (1984); b) O. Tanaka, R. Kasai, and T. Morita, Chemistry of ginseng and related plants: recent advances, Abstracts of Chinese Medicines (The Chinese University of Hong Kong), 1:130 (1986); c) O. Tanaka, Recent studies on glycosides from plant drugs of Hymalaya and southwestern China. Chemo-geographical correlation of Panax species, Pure and Appl. Chem., 62:1281 (1990).
2. S. Shibata, O. Tanaka, J. Shoji, and H: Saito, Economic and Medicinal Plant Research, Vol. I, Academic Press, Inc. ( London) Ltd., (1985).
3. D. K. Long, Information about a new Panax species discovered in Kon Turn province of Vietnam, unpublished document of the Fifth Zone Health Service of Vietnam (1973).
4. H. T. Dung, and I. V. Grushvitsky, Panax vietnamensis, a new Panax species, J. Vietnam Bot., 4: 518 (1985).
5. N. T. Nham, P. V. De, T. C. Luan, N. M. Duc, S. Shibata, O. Tanaka, and R. Kasai, Pharmacognostical and chemical studies on Vietnamese ginseng, Panax vietnamensis Ha et Grushv. (Araliaceae), J. Japn. Bot., 70: 1 (1995).