@article{onthecomplexityoffindingsecondbest,
  title = {On the Complexity of Finding Second-Best Abductive Explanations},
  author = {Paolo Liberatore and Marco Schaerf},
  year = {2012},
  eprint = {1204.5859},
  archivePrefix = {arXiv},
  url = {http://arxiv.org/abs/1204.5859v3},
}