1. Ades TB (ed) (2009) Aromatherapy. American Cancer Society complete guide to complementary and alternative cancer therapies, 2nd edn. American Cancer Society, Atlanta, pp 57–60
2. Alam Z (2008) Herbal medicines. A.P.H. Publishing, New Delhi, p 122
3. Anonymous (2013) In: Semple D, Smyth R (eds) Oxford handbook of psychiatry, 3rd edn. Oxford University Press, Oxford, p 20
4. Bausell RB (2007) Snake oil science: the truth about complementary and alternative medicine. Oxford University Press, Oxford, p 259
5. Bennett RN, Wallsgrove RM (1994) Secondary metabolites in plant defence mechanisms. New Phytol 127:617–633