R. Brooks, C. Woods, D. Benjamin, and N. Rosenstein. Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America, 43 (1):
49--54(July 2006)PMID: 16758417.
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.