1. Kearns P, Siebert S, Willicombe M, et al. Examining the immunological effects of covid-19 vaccination in patients with conditions potentially leading to diminished immune response capacity. Preprints with the Lancet 2021 [preprint]. https://papers.ssrn.com/sol3/papers.cfm?abstract_id=3910058 "https://www.thelancet.com/preprints"
2. Covid-19 booster vaccines: What we know and who’s doing what