Sazgary, L., A. Meienberg, C. T. Berger, and M. Mayr. “The Meaning of SARS-CoV-2 Antibodies in a Patient With a Systemic Reaction to the MRNA-1273 SARS-CoV-2 Vaccine After Previous Natural Immunization ”. European Journal of Case Reports in Internal Medicine, vol. 8, no. 6, June 2021, doi:10.12890/2021_002617.