@Article{jue:07a,    
  author = 	 {Z.\ \v{S}\'\i r and B.\ J\"uttler},
  title = 	 {${C}^2$ {H}ermite interpolation by spatial {P}ythagorean hodograph curves},
  journal = 	 {Math. Comp.},
  year = 	 {2007},
  volume =	 {76},
  pages =	 {1373--1391},
}