@article{JMLR:v10:langford09a,
  author  = {John Langford and Lihong Li and Tong Zhang},
  title   = {Sparse Online Learning via Truncated Gradient},
  journal = {Journal of Machine Learning Research},
  year    = {2009},
  volume  = {10},
  number  = {28},
  pages   = {777--801},
  url     = {http://jmlr.org/papers/v10/langford09a.html}
}