@article{primaldualactivesetmethodsforisotonic,
  title = {Primal-Dual Active-Set Methods for Isotonic Regression and Trend Filtering},
  author = {Zheng Han and Frank E. Curtis},
  year = {2015},
  eprint = {1508.02452},
  archivePrefix = {arXiv},
  url = {http://arxiv.org/abs/1508.02452v2},
}