1. Miller NS, Cocores JA. Nicotine dependence: Diagnosis, chemistry, and pharma-cologic treatments.Pediatrics in Review 1993; 14: 275.
2. National Institute on Drug Abuse, National Institutes of Health, United States; Cigarettes and other nicotine products, NIDA Infofax,www.nida.nih.gov, accessed 7/19/1999
3. National Cancer Institute, USA : Environmental tobacco smoke,www.nci.nih. gov, accessed 7/19/1999.
4. Holbrook JH. Nicotine addiction. In: Fauci AS, Braunwald E, Isselbacher KJet al (eds).Harrison’s Principles of Internal Medicine, 14th edn. Mc-Graw Hill, New Delhi 1998; pp 2516.
5. Epps RP, Lunn WR, Manley MW. Tobacco, youth, and sports.Adolescent Medicine 1998; 9:483.