@article{alinearapproximationtothechi2kernel,
  title = {A Linear Approximation to the chi^2 Kernel with Geometric Convergence},
  author = {Fuxin Li and Guy Lebanon and Cristian Sminchisescu},
  year = {2012},
  eprint = {1206.4074},
  archivePrefix = {arXiv},
  url = {http://arxiv.org/abs/1206.4074v3},
}