1. Peters KO, Kochonek KD, Murphy SC. Deaths: final data for 1996. Hyattsville, MD: National Center for Health Statistics, National Vital Statistics Report (vol 47) 1998; DHHS Publication No. (PHS) 99–1120
2. 1998 fact book;National Heart, Lung, and Blood Institute,1999
3. Statistical abstract of the United States, 1997;US Bureau of the Census,1997
4. Morbidity and mortality: chart book on cardiovascular, lung, and blood diseases;National Heart, Lung, and Blood Institute,1998
5. An economic evaluation of asthma in the United States;Weiss;N Engl J Med,1992