Effectiveness of Covid-19 Vaccines against the B.1.617.2 (Delta) Variant.
N Engl J Med. 2021 Aug 12;385(7):585-594. doi: 10.1056/NEJMoa2108891. Epub 2021 Jul 21.
N Engl J Med. 2021.
PMID: 34289274
Free PMC article.