1. Guenther, E. 1950.The Essential Oils, Vol. 5, 135–160. New York: D. Van Nostrand Co., Inc.
2. Pepper — chemistry, technology, and quality evaluation
3. Purseglove, J. W., Brown, E. G., Green, C. L. and Robbins, S. R.J. 1981.Spices, Vol. 1, 46–59. London: Longman Group Ltd.
4. Lawrence, B. M. 1981.Essential Oils 1979–1980, 196–228. Wheaton, IL, USA: Allured Publishing Corp.
5. 1984.Official Methods of Analysis,, 14th Ed., 563–572. Arlington, VA, USA: Association of Official Analytical Chemists, Inc.