@article{Bloch:2010XC,
  author = "Bloch, Jacques  and  Breu, Tobias  and  Frommer, Andreas  and  Heybrock, Simon  and  Schäfer, Katrin  and  Wettig, Tilo",
  title = "{Krylov subspace methods and the sign function: multishifts and deflation in the nonhermitian case}",
  doi = "10.22323/1.091.0043",
  journal = "PoS",
  year = 2010,
  volume = "LAT2009",
  pages = "043"
}