Safety and immunogenicity of seven COVID-19 vaccines as a third dose (booster) following two doses of ChAdOx1 nCov-19 or BNT162b2 in the UK (COV-BOOST): a blinded, multicentre, randomised, controlled, phase 2 trial
2021 · The Lancet · 673 citations
https://doi.org/10.1016/s0140-6736(21)02717-3