1. CDC. Center for disease control and prevention, outbreak of swine-origin influenza A (H1N1) virus infection -Mexico, March–April 2009. Morb Mortal Wkly Rep. 2009;58:467–470 Available from: http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5817a5.htm.
2. CDC. Center for disease control and prevention, flu news & spotlights, first global estimates of 2009 h1n1 pandemic mortality released by cdc-led collaboration. Atlanta (GA): CDC. Available from: http://www.cdc.gov/flu/spotlights/pandemic-global-estimates.htm (cited 2013 May 10).
3. WHO. Influenza: Influenza Update N° 185 [internet]. Geneva: WHO. Available from: http://www.who.int/influenza/surveillance_monitoring/updates/2013_05_10_surveillance_update_185.pdf (cited 2013 May 10).
4. Estimating the Burden of 2009 Pandemic Influenza A (H1N1) in the United States (April 2009-April 2010)