@inproceedings{GK95,
  title = "Three-processor tasks are undecidable",
  author = "E. Gafni and E. Koutsoupias",
  year = "1995",
  address = "Ottawa, Ontario, Canada",
  booktitle = "Proceedings of the Fourteenth Annual ACM Symposium on Principles of Distributed Computing",
  month = "20--23 aug",
  note = "Final version in Siam J. on Comp.",
  pages = "271",
}