1. Centers for Disease Control and Prevention. National surveillance of asthma: United States, 2001-2010. http://www.cdc.gov/nchs/data/series/sr_03/sr03_035.pdf. Accessed April 2, 2013.
2. Asthma in the elderly: current understanding and future research needs—a report of a national institute on aging workshop;Hanania;J Allergy Clin Immunol,2011
3. Asthma and Allergy Foundation of America. Older adults and asthma. http://www.aafa.org/display.cfm?id=8&sub=17&cont=173. Accessed September 3, 2013.
4. Age-related differences in clinical outcomes for acute asthma in the United States, 2006-2008;Tsai;J Allergy Clin Immunol,2012
5. US Health and Human Services. Administration on Aging. Aging statistics. http://www.aoa.gov/Aging_Statistics/Profile/2012/3.aspx. Accessed June 15, 2013.