A. Petsas, A. Sharma, O. Aghadiuno, M. Abid, and K. Paranthaman. Euro Surveillance: Bulletin Européen Sur Les Maladies Transmissibles = European Communicable Disease Bulletin, (January 2008)PMID: 18445400.
F. Fusco, and V. Puro. Euro Surveillance: Bulletin Européen Sur Les Maladies Transmissibles = European Communicable Disease Bulletin, (March 2008)PMID: 18445438.