@inproceedings{smi-bor-02-htnorm,
  author = {Gavin D.J. Smith and Adrian G. Bors},
  title = {Height Estimation from Vector Fields of Surface Normals},
  booktitle = {Proc. 2002 IEEE International Conference on Digital Signal Processing (DSP'02)},
  location = {Santorini, Greece},
  year = 2002,
  pages = {1031--1034},
  comment = {Uses an iterative local method, similar to Poisson but perhaps nonlinear.  They are not aware that it takes forever to converge. Plots residual of normals and uses it as a convergence criterion, but fails to realize that it does not tell anything about the height residual. Moreover uses a cosine metric to show convergence but fails to notice that cosine 0.92 --- after 20.000 iterations --- means an error of 20 degrees.  Probably the height map is miles (literally) avaw from convergence but they did not notice it because they did not compare with ground truth.}
}