1. Canter, H. P., Thomas, H., & Ernst, E. (2005). Trends in Biotechnology, 23, 180–185.
2. Edwards, R. (2004). New Scientist (1971), 181, 10–11.
3. Jirovetz, L., Gerhard, B., Shafi, P. M., & Leela, N. K. (2003). Acta Pharmaceutica, 53, 73–81.
4. Amandeep, K., Ranvir, S., Chinmoy, S. D., Shyam, S. S., Kamlesh, K. B., & Inder, P. S. (2010). Indian Journal of Experimental Biology, 48, 314–317.
5. Janssen, A. M., & Scheffer, J. J. C. (1985). Planta Medica, 6, 507–511.