@article{albert2000jamming,
  title={Jamming and fluctuations in granular drag},
  author={Albert, I and Tegzes, P and Kahng, B and Albert, R and Sample, JG and Pfeifer, M and Barab{\'a}si, A-L and Vicsek, T and Schiffer, P},
  journal={Physical Review Letters},
  volume={84},
  number={22},
  pages={5122},
  year={2000},
  publisher={American Physical Society}
}