1. •     JHU CSSE COVID-19 Data
2. •     https://www.jnj.com/johnson-johnson-single-shot-covid-19-vaccine-phase-3-data-published-in-new-england-journal-of-medicine
3. •     https://www.jnj.com/our-company/johnson-johnson-announces-its-first-phase-3-covid-19-vaccine-trial-ensemble-is-fully-enrolled
4. •     https://www.yalemedicine.org/news/covid-19-vaccine-comparison
5. •     https://417studies.com/how-long-do-clinical-trials-take/
6. •     https://www.pfizer.com/news/press-release/press-release-detail/pfizer-and-biontech-conclude-phase-3-study-covid-19-vaccine
7. •     https://www.cdc.gov/mmwr/volumes/69/wr/mm6950e2.htm?s_cid=mm6950e2_w
8. •     https://www.who.int/news-room/feature-stories/detail/vaccine-efficacy-effectiveness-and-protection
9. •     https://www.euro.who.int/en/health-topics/health-emergencies/coronavirus-covid-19/novel-coronavirus-2019-ncov
10. •     https://www.who.int/news-room/feature-stories/detail/the-effects-of-virus-variants-on-covid-19-vaccines
11.