@inproceedings{ijcai2005p205,
  title     = {Concurrent Hierarchical Reinforcement Learning},
  author    = {Marthi, Bhaskara and Russell, Stuart J. and Latham, David and Guestrin, Carlos},
  booktitle = {Proceedings of the Nineteenth International Joint Conference on
               Artificial Intelligence, {IJCAI-05}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  pages     = {779--784},
  year      = {2005},
  url       = {https://ijcai.org/proceedings/2005/205},
}