@Article{	  Schweitzer:2009*1,
  author	= {M.~A. Schweitzer},
  title		= {{An Algebraic Treatment of Essential Boundary Conditions
		  in the Particle--Partition of Unity Method}},
  journal	= {SIAM Journal on Scientific Computing},
  year		= {2009},
  volume	= {31},
  pages		= {1581-1602},
  number	= {2},
  annote	= {article,ag-schweitzer},
  doi		= {10.1137/080716499},
  http		= {http://link.aip.org/link/?SCE/31/1581},
  pdf		= {http://wissrech.ins.uni-bonn.de/research/pub/schweitz/algebraicboundaryconditions.pdf}
		  
}