B. Jülg, J. Elias, A. Zahn, S. Köppen, C. Becker-Gaab, and J. Bogner. Journal of Travel Medicine: Official Publication of the International Society of Travel Medicine and the Asia Pacific Travel Health Association, 15 (2):
133--6(2008)PMID: 18346250.
S. Shehab, N. Keller, A. Barkay, L. Leitner, A. Leventhal, and C. Block. European Journal of Clinical Microbiology & Infectious Diseases: Official Publication of the European Society of Clinical Microbiology, 17 (11):
749--53(November 1998)PMID: 9923513.
WHO. Relevé Épidémiologique Hebdomadaire / Section D'hygiène Du Secrétariat De La Société Des Nations = Weekly Epidemiological Record / Health Section of the Secretariat of the League of Nations, 81 (13):
119--120(March 2006)PMID: 16673512.