@article{whendoesamixtureofproductscontaina,
  title = {When Does a Mixture of Products Contain a Product of Mixtures?},
  author = {Guido F. Montufar and Jason Morton},
  year = {2012},
  eprint = {1206.0387},
  archivePrefix = {arXiv},
  url = {http://arxiv.org/abs/1206.0387v5},
}