Jan Erik Solem Henrik Aanæs Anders Heyden Variational Surface Interpolation from Sparse Point and Normal Data. 181-184 2007 29 IEEE Trans. Pattern Anal. Mach. Intell. 1 http://doi.ieeecomputersociety.org/10.1109/TPAMI.2007.23 db/journals/pami/pami29.html#SolemAH07