@inproceedings{groupsparsecoding,
  title = {Group Sparse Coding},
  author = {Samy Bengio and Fernando Pereira and Yoram Singer and Dennis Strelow},
  year = {2009},
  booktitle = {NeurIPS 2009 12},
  url = {http://papers.nips.cc/paper/3691-group-sparse-coding},
}