@article{albert2001stick, title={Stick-slip fluctuations in granular drag}, author={Albert, I and Tegzes, P and Albert, R and Sample, JG and Barab{\'a}si, A-L and Vicsek, T and Kahng, B and Schiffer, P}, journal={Physical Review E}, volume={64}, number={3}, pages={031307}, year={2001}, publisher={American Physical Society} }