1. I. A. Ogunwande, G. Flamini, N. O. Avoseh, and I. B. Banwo, Chem. Nat. Compd., 50, 373 (2014).
2. British Pharmacopoeia II, P.A. 109, H. M. Stationary Office, London, 1980.
3. R. P. Adams, Identification of Essential Oil Components by Gas Chromatography/Quadrupole Mass Spectrometry, Allured Publishing Corp. Carol Stream, IL, 2007, 275 pp.
4. D. Joulain and W. A. Koenig, The Atlas of Spectral Data of Sesquiterpene Hydrocarbons, E. B. Verlag, Hamburg, 2008, 254 pp.
5. National Institute of Standards and Technology, Chemistry Web Book, Data from NIST Standard Reference Database 69, 2011, http://www.nist.gov/ .