1. WHO: World Health Organization: Influenza (seasonal) fact sheet 211. 2009, http://www.whoint/mediacentre/factsheets/fs211/en/2009 April 1Fact Sheet(211)Available from: URL: http://www.who.int/mediacentre/factsheets/fs211/en/ .
2. ECDC. European Centre for Disease Prevention and Control: Seasonal human influenza and vaccination - the facts. 2007, http://ecdc.europa.eu/en/healthtopics/documents/0712_seasonal_human_influenza_vaccination.pdf ,
3. GROG: Estimation GROG du coût direct de l’épidemie de grippe 2005/2006. 2007, Paris: Réseau des GROG - Groupes Régionaux d’Observation de la Grippe, Available on: http://openrome.org/documents/eco/2007_JNI_poster_ecogrippe.pdf
4. GROG: Situation de la grippe en France pour la semaine 2011/6. 2013, Paris: Groupes Régionaux d’Observation de la Grippe, Available on http://www.grog.org/cgi-files/db.cgi?code=352&ction=bulletin_grog
5. Fleming DM, Zambon M, Bartelds AI, de Jong JC: The duration and magnitude of influenza epidemics: a study of surveillance data from sentinel general practices in England, Wales and the Netherlands. Eur J Epidemiol. 1999, 15 (5): 467-473. 10.1023/A:1007525402861.