@article { Guarracino2006IJAMCS,
  author =      "Guarracino, M. R. and Perla, F. and Zanetti, P.",
  title =       "A parallel block Lanczos algorithm and its implementation for the evaluation of some eigenvalues of large sparse symmetric matrices on multicomputers",
  journal =     "International Journal of Applied Mathematics and Computer Science",
  volume =      "16",
  number =      "2",
  pages =       "241--249",
  year =        "2006"
  }