1. Editorial Committee of the Administration Bureau of Chinese Plant Medicine, ‘Chinese Flora’, Science Press, Beijing, 1979, Vol. 75, p. 249.
2. Editorial Committee of the Administration Bureau of Chinese Flora, ‘Chinese Flora’, Science Press, Beijing, 1979, Vol. 75, p. 254;
3. , , ‘ Herbal Medicine’, The Pharmaceautical Press, London, 1996.
4. ‘A Comprehensive Dictionary of Traditional Chinese Materia Medica’, Shanghai People's Press, 1977, Vol. 1, p. 81.
5. Chlorinated thymol derivatives from Inula crithmoides