J. Band, D. Fraser, A. Hightower, and C. Broome. JAMA: The Journal of the American Medical Association, 252 (23):
3249--50(December 1984)PMID: 6334756.
P. Gastmeier, D. Sohr, C. Geffers, M. Behnke, and H. Rüden. Infection Control and Hospital Epidemiology: The Official Journal of the Society of Hospital Epidemiologists of America, 28 (4):
466--72(April 2007)PMID: 17385154.