1. Akehurst, B C. 1981.Tobacco. 2nd ed. Tropical Agricultural Series, 164New York: Longman Inc.
2. Association of Official Analytical Chemists (AOAC). 1997.Official methods of analysis, 14th ed, 1298Arlington, VA: AOAC.
3. Chari, M S. 1995.Role of research in the improvement of productivity and quality of Indian flue-cured Virginia tobacco, 26Rajahmundry, India: Central Tobacco Research Institute.
4. Collins, W K and Hawks, S N Jr. 1993.Principles of flue-cured tobacco production, 212Raleigh, NC: North Carolina State University.