Hofhuis A, van der Giessen J W B, Borgsteede F H M, Wielinga P R, Notermans D W, van Pelt W
Centre for Infectious Disease Control, National Institute for Public Health and the Environment Bilthoven, The Netherlands.
Euro Surveill. 2006 Jun 22;11(6):E060622.2. doi: 10.2807/esw.11.25.02978-en.