@article{Ruetalo_2021,
title={Long-Term Humoral Immune Response against SARS-CoV-2 after Natural Infection and Subsequent Vaccination According to WHO International Binding Antibody Units (BAU/mL)},
volume={13},
ISSN={1999-4915},
url={http://dx.doi.org/10.3390/v13122336},
DOI={10.3390/v13122336},
number={12},
journal={Viruses},
publisher={MDPI AG},
author={Ruetalo,
Natalia and Flehmig,
Bertram and Schindler,
Michael and Pridzun,
Lutz and Haage,
Angelika and Reichenbächer,
Marija and Kirchner,
Thomas and Kirchner,
Teresa and Klingel,
Karin and Ranke,
Michael B. and Normann,
Andrea},
year={2021},
month=nov,
pages={2336} }