@article{N^3,
  author = "Nicholas Hale, Nicholas J. Higham and Lloyd N. Trefethen",
  doi = "10.1137/070700607",
  journal = "SIAM Journal on Numerical Analysis",
  mrnumber = "5",
  pages = "2505--2523",
  title = "Computing $A^\alpha, \log(A)$, and Related Matrix Functions by Contour Integrals",
  volume = "46",
  year = "2008",
}