1. Adams, R.P. (1995).Identification of essential oils components by Gas chromatography/Mass spectroscopy. Allured Publishing Co. Carol Stream, Illinois.
2. Hutchinson, J., Dalziel, J.M. (1954).Flora of West Tropical Africa. Nelson T and Sons (eds), London.
3. Jennings, W., Shibamoto, T. (1980).Quantitative analysis of flavour and fragrance volatiles by glass capillary gas chromatography. Academic Press: New York.