@Article{jue:11c,
  author =  {T. Takacs and B. J\"uttler},
  title =   {Existence of Stiffness Matrix Integrals for Singularly 
             Parameterized Domains in Isogeometric Analysis},
  journal = {Computer Methods in Applied Mechanics and Engineering},
  volume =  {200},
  year =    {2011},
  pages ={3568-3582},
  DOI = {10.1016/j.cma.2011.08.023}}