@article{Ozogany2014,
  title={Modeling the emergence of modular leadership hierarchy during the collective motion of herds made of harems},
  author={Ozogany, Kata and Vicsek, Tam{\'a}s },
  journal={J. Stat. Phys},
  volume={158},
  number={},
  pages={628-646},
  year={2015},
}