@article{sapiezynski2015tracking,
  title={Tracking human mobility using wifi signals},
  author={Sapiezynski, Piotr and Stopczynski, Arkadiusz and Gatej, Radu and Lehmann, Sune},
  journal={PloS one},
  volume={10},
  number={7},
  pages={e0130824},
  year={2015},
  publisher={Public Library of Science}
}