1[1]Coronavirus never before seen in humans is the cause of SARS. 16 April 2003, http: ∥www. who. int/csr/sars/arehive/2003 04 16/en/
2[2]First data on stability and resistance of SARS coronavirus compiled by members of WHO laboratory network. 4 May 2003, http: ∥ www. who. int/csr/sars/survival 2003 05 04/en/index. html
3[3]One month into the global SARS outbreak: Status of the outbreak and lessons for the immediate future. April 11, 2003, http: ∥ www. who. int/csr/sarsarchive/2003 04 11/en/
4[4]SARS case fatality ratio, incubation period. 7 May 2003, http : ∥ www . who.int/csr/sarsarchive/2003 05 07a/eh/
