@article{farkas2001spectra,
  title={Spectra of “real-world” graphs: Beyond the semicircle law},
  author={Farkas, Illes J and Der{\'e}nyi, Imre and Barab{\'a}si, Albert-L{\'a}szl{\'o} and Vicsek, Tamas},
  journal={Physical Review E},
  volume={64},
  number={2},
  pages={026704},
  year={2001},
  publisher={American Physical Society}
}