@Article{	  Burstedde:2007,
  author	= {Carsten Burstedde},
  title		= {On the numerical evaluation of fractional {S}obolev
		  norms},
  journal	= {Communications on Pure and Applied Analysis},
  year		= {2007},
  volume	= {6},
  pages		= {587-605},
  number	= {3}
}