@article{janssen_nachreiner_2004,  title={Health and psychosocial effects of flexible working hours},  volume={38},  ISSN={0034-8910},  url={https://doi.org/10.1590/S0034-89102004000700003},  DOI={10.1590/S0034-89102004000700003},  journal={Revista de Saúde Pública},  publisher={Faculdade de Saúde Pública da Universidade de São Paulo},  author={Janssen, Daniela and Nachreiner, Friedhelm},  year={2004},  month={Dec},  pages={11–18} }