@article{VossKurthsSchwarz1996,
  author    = {Henning U. Voss and J{\"u}rgen Kurths and Udo Schwarz},
  title     = {Reconstruction of grand minima of solar activity from radiocarbon data : linear and nonlinear signal analysis},
  url       = {http://www.agnld.uni-potsdam.de/~shw/Paper/vks.ps.gz},
  year      = {1996},
}