Seyler T, Rizzo C, Finarelli A C, Po C, Alessio P, Sambri V, Ciofi Degli Atti M L, Salmaso S
Communicable Disease Epidemiology Unit, National Centre of Epidemiology, Surveillance and Health Promotion, Istituto Superiore di Sanita (National Public Health Institute, ISS), Rome, Italy.
Euro Surveill. 2008 Jan 17;13(3):8015. doi: 10.2807/ese.13.03.08015-en.