@inproceedings{ijcai2015p124,
  title     = {Building Hierarchies of Concepts via Crowdsourcing},
  author    = {Sun, Yuyin and Singla, Adish and Fox, Dieter and Krause, Andreas},
  booktitle = {Proceedings of the Twenty-Fourth International Joint Conference on
               Artificial Intelligence, {IJCAI-15}},
  publisher = {International Joint Conferences on Artificial Intelligence},
  editor    = {Qiang Yang and Michael Wooldridge},
  pages     = {844--852},
  year      = {2015},
  month     = {7},
  note      = {Main Track},
  url       = {https://ijcai.org/proceedings/2015/124},
}