@article{MancarelleEtAlTPLP2009,
  author =        {Paolo Mancarella and Giacomo Terreni and Fariba Sadri and Francesca Toni and Ulle Endriss},
  title =         {The CIFF Proof Procedure for Abductive Logic Programming with Constraints: Theory, Implementation and Experiments},
  journal =       {Theory and Practice of Logic Programming},
  volume =        {9},
  number =        {6},
  pages =         {691--750},
  year =          {2009},
  doi =           {10.1017/S1471068409990093}
}