22.https://www.technologyreview.com/2020/08/13/1006314/take-your-best-shot/
23.https://www.bloomberg.com/news/articles/2020-05-13/u-s-to-get-sanofi-covid-vaccine-first-if-it-succeeds-ceo-says
24.https://www.nytimes.com/2020/05/04/world/europe/eu-coronavirus-vaccine.html
25.https://www.bbc.com/news/world-europe-52525387
26.https://www.guancha.cn/ChanJing/2020_05_29_552196.shtml
27.https://endpts.com/covid-19-roundup-chinas-sinopharm-ready-to-talk-price-doses-as-ceo-predicts-december-rollout-eu-launches-e77-7m-search-for-more-drugs/
28.https://news.stcn.com/sd/202008/t20200818_2236027.html
29.https://www.cnn.com/2020/08/13/europe/russia-us-coronavirus-vaccine/index.html
