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.
J. Bigham, M. Hutcheon, D. Patrick, and A. Pollard. Canada Communicable Disease Report = Relevé Des Maladies Transmissibles Au Canada, 27 (2):
13--8(January 2001)PMID: 11227821.
M. Bonten, D. Austin, and M. Lipsitch. Clinical Infectious Diseases: An Official Publication of the Infectious Diseases Society of America, 33 (10):
1739--46(November 2001)PMID: 11595995.
D. Schlierkamp-Voosen, and H. Mühlenbein. Proceedings of the 3rd Conference on Parallel Problem Solving from Nature, 866, page 199--208. Springer, Berlin, Heidelberg, New York, (1994)