@article{groupsparsemodelselectionhardnessand,
  title = {Group-Sparse Model Selection: Hardness and Relaxations},
  author = {Luca Baldassarre and Nirav Bhan and Volkan Cevher and Anastasios Kyrillidis and Siddhartha Satpathi},
  year = {2013},
  eprint = {1303.3207},
  archivePrefix = {arXiv},
  url = {http://arxiv.org/abs/1303.3207v4},
}