@incollection {NIPS2003_AA45,
  author = " Tom Heskes and  Onno Zoeter and  Wim Wiegerinck",
  title = " Approximate Expectation Maximization",
  booktitle = "Advances in Neural Information Processing Systems 16",
  editor = "Sebastian Thrun and Lawrence Saul and Bernhard {Sch\"{o}lkopf}",
  publisher = "MIT Press",
  address = "Cambridge, MA",
  year = "2004",
  keywords = "EM algorithm, approximate inference, Bethe free energy, Kikuchi free energy, convergence, variational methods",
  }