1. NHS. Letter to chief executives of all NHS trusts and foundation trusts. 30 Dec 2020. https://www.england.nhs.uk/coronavirus/wp-content/uploads/sites/52/2020/12/C0994-System-letter-COVID-19-vaccination-deployment-planning-30-December-2020.pdf.
2. Department for Health and Social Care. Letter to the profession from the UK chief medical officers regarding the UK covid-19 vaccination programmes. 31 Dec 2020. https://www.gov.uk/government/publications/letter-to-the-profession-from-the-uk-chief-medical-officers-on-the-uk-covid-19-vaccination-programmes/letter-to-the-profession-from-the-uk-chief-medical-officers-regarding-the-uk-covid-19-vaccination-programmes.
3. Supplementary appendix. https://www.thelancet.com/cms/10.1016/S0140-6736(20)32661-1/attachment/4fb6f146-1b38-48e0-89cb-213bc4dca7ec/mmc1.pdf.
4. Safety and efficacy of the ChAdOx1 nCoV-19 vaccine (AZD1222) against SARS-CoV-2: an interim analysis of four randomised controlled trials in Brazil, South Africa, and the UK
5. Safety and Efficacy of the BNT162b2 mRNA Covid-19 Vaccine