1. J. Bruneton, Pharmacognosy, Phytochemistry, Medical Plants, Lavoisier, New York (1999), p. 1119.
2. G. F. Krylov, Herbs of Life and Their Seekers [in Russian], Novosibirsk (1972), p. 263.
3. T. Eicher, S. Fey, W. Puhl, E. Buchel, and A. Speicher, Eur. J. Org. Chem., 877 (1998).
4. Z.-Q. Lu, P.-H. Fan, M. Ji, and H.-X. Lou, J. Asian Nat. Prod. Res., 8, No. 1–2, 187 (2006).
5. H. D. Zinsmeister, H. Becker, and T. Eicher, Angew. Chem., 103, 134; Angew. Chem. Int. Ed. Engl., 30, 130 (1991).