@article{JMLR:v10:drton09a,
  author  = {Mathias Drton and Michael Eichler and Thomas S. Richardson},
  title   = {Computing Maximum Likelihood Estimates in Recursive Linear Models with Correlated Errors},
  journal = {Journal of Machine Learning Research},
  year    = {2009},
  volume  = {10},
  number  = {81},
  pages   = {2329--2348},
  url     = {http://jmlr.org/papers/v10/drton09a.html}
}