@ARTICLE{10.3389/fimmu.2021.635522, AUTHOR={von Mutius, Erika}, TITLE={The “Hygiene Hypothesis” and the Lessons Learnt From Farm Studies}, JOURNAL={Frontiers in Immunology}, VOLUME={12}, YEAR={2021}, URL={https://www.frontiersin.org/articles/10.3389/fimmu.2021.635522}, DOI={10.3389/fimmu.2021.635522}, ISSN={1664-3224} }