1. :Causes of COVID-19: https://www.mayoclinic.org/diseases-conditions/coronavirus/symptoms-causes/syc-20479963.
2. COVID-19 CORONAVIRUS / CASES: Available at:https://www.worldometers.info/coronavirus/coronavirus-cases/.
3. Mathematical modeling of the spread of the coronavirus disease 2019, (COVID-19) considering its particular characteristics. The case of China, MOMAT;Ivorra,2020
4. Coronavirus poster: https://www.who.intdocscoronavirus-poster-english-srilanka.
5. Media Statement: Knowing the risks for COVID-19: Available at:https://www.who.intknowing-the-risk-for-covid-19.