@InProceedings{Torre97prohaireticdeontic,
  Title                    = {Prohairetic Deontic Logic and Qualitative Decision Theory},
  Author                   = {Torre, L.W.N. van der and Yao-hua Tan},
  Booktitle                = {In Proceedings of the AAAI Spring Symposium on Qualitative Approaches to Deliberation and Reasoning},
  Year                     = {1997},
  Publisher                = {AAAI Press},

  Url                      = {http://icr.uni.lu/leonvandertorre/papers/aaai97.ps.Z}
}