@article{topologicalgrammarsfordataapproximation,
  title = {Topological Grammars for Data Approximation},
  author = {A. N. Gorban and N. R. Sumner and A. Y. Zinovyev},
  year = {2006},
  eprint = {cs/0603090},
  archivePrefix = {arXiv},
  url = {https://arxiv.org/abs/cs/0603090v2},
}