1. Von Mutius E. Influences in allergy: epidemiology and the environment. J Allergy Clin Immunol 2004;113:373–9
2. Martinez FD. Development of wheezing disorders and asthma in preschool children. Pediatrics 2002;109:362–7
3. Gern J, Busse WW. The role of viral infections in the natural history of asthma. J Allergy Clin Immunol 2000;106:201–12
4. Piedra PA, Englund JA, Glezen WP. Respiratory syncytial virus and parainfluenza viruses. In: Richman DD, Whitley RJ, Hayden FG (eds) Clinical Virology. ASM Press, Washington, 2002, p763
5. Gwaltney JM Jr, Heinz BA. Rhinovirus. In: Richman DD, Whitley RJ, Hayden FG (eds) Clinical Virology. ASM Press, Washington, 2002, p 995.