1. World Health Organization (WHO).http://www.who.int/news-room/fact-sheets/detail/influenza-(avian-and-other-zoonotic)
2. Centers for Disease Control and Prevention (CDC).https://www.cdc.gov/flu/avianflu/influenza-a-virus-subtypes.htm
3. Chinese Centers for Disease Control and Prevention (China CDC).http://www.chinacdc.cn/
4. Chinese Centers for Disease Control and Prevention (China CDC).http://www.chinacdc.cn/jkzt/crb/zl/rgrgzbxqlgg/rgrqlgyp/