1. K. Bremer and C. J. Humphries, Bull. Br. Mus. (Nat. Hist.) Bot., 23 (2), 71 (1993).
2. H. Duman, Edinburg Univ. Press, Edinburg, 11, 158, 319 (2000).
3. M. Wichtl, Herbal Drugs and Phytopharmaceuticals, Third Ed., Stuttgart, Germany, 2004, 707 pp.
4. M. J. R. Howes, N. S. L. Perry, and P. J. Houghton, Phy. Res.,17, 1 (2003).
5. E. Khazneh, G. Saltan, M. Tekin, O. B. Acikara, T. Yesiloglu, and S. Ozbilgin, J. Fac. Pharm. Ankara Univ.,39 (1), 43 (2010).