message: Some references for sparse Rips.
diff: @@ -1070,5 +1070,36 @@ language={English}
  year = {2015}
  }
  -
  -
  +@article{buchet16efficient,
  + Title = {Efficient and Robust Persistent Homology for Measures},
  + Author = {Micka\"{e}l Buchet and Fr\'{e}d\'{e}ric Chazal and Steve Y. Oudot and Donald Sheehy},
  + Booktitle = {Computational Geometry: Theory and Applications},
  + Volume = {58}
  + Pages = {70--96}
  + Year = {2016}
  +}
  +
  +@inproceedings{cavanna15geometric,
  + Author = {Nicholas J. Cavanna and Mahmoodreza Jahanseir and Donald R. Sheehy},
  + Booktitle = {Proceedings of the Canadian Conference on Computational Geometry},
  + Title = {A Geometric Perspective on Sparse Filtrations},
  + Year = {2015}
  +}
  +
  +@inproceedings{cavanna15visualizing,
  + Author = {Nicholas J. Cavanna and Mahmoodreza Jahanseir and Donald R. Sheehy},
  + Booktitle = {Proceedings of the 31st International Symposium on Computational Geometry},
  + Title = {Visualizing Sparse Filtrations},
  + Year = {2015},
  + doi = {10.4230/LIPIcs.SOCG.2015.23}
  +}
  +
  +@article{sheehy13linear,
  + Title = {Linear-Size Approximations to the {V}ietoris-{R}ips Filtration},
  + Author = {Donald R. Sheehy},
  + Journal = {Discrete \& Computational Geometry},
  + Volume = {49},
  + Number = {4},
  + Pages = {778--796},
  + Year = {2013}
  +}
  