@article{SeehaferFuhrmannValorietal.2007,
  author    = {Norbert Seehafer and M. Fuhrmann and Gherardo Valori and Bernhard Kliem},
  title     = {Force-free magnetic fields in the solar atmosphere},
  url       = {http://www3.interscience.wiley.com/cgi-bin/abstract/117872628/ABSTRACT},
  year      = {2007},
}