1. WHO timeline—COVID-19https://www.who.int/news-room/detail/27-04-2020-who-timeline---COVID-19
2. Coronavirus (2019-nCoV) (MedicineNet)https://www.medicinenet.com/wuhan_coronavirus_2019-ncov/article.htm
3. COVID-19 Coronavirus Pandemic (Worldometer)https://www.worldometers.info/coronavirus/
4. Coronavirus Disease (COVID-19)—Events as They Happenhttps://www.who.int/emergencies/diseases/novel-coronavirus-2019/events-as-they-happen