@article{JMLR:v13:kumar12a,
  author  = {Sanjiv Kumar and Mehryar Mohri and Ameet Talwalkar},
  title   = {Sampling Methods for the Nyström Method},
  journal = {Journal of Machine Learning Research},
  year    = {2012},
  volume  = {13},
  number  = {34},
  pages   = {981--1006},
  url     = {http://jmlr.org/papers/v13/kumar12a.html}
}