@inproceedings{Herbelin05a,
  author      = {Hugo Herbelin},
  title       = {On the Degeneracy of Sigma-Types in Presence of Computational
                 Classical Logic},
  booktitle   = {Seventh International Conference, TLCA '05, Nara, Japan.
                 April 2005, Proceedings},
  editor      = {Pawel Urzyczyn},
  pages       = {209--220},
  publisher   = {Springer},
  series      = {Lecture Notes in Computer Science},
  volume      = {3461},
  year        = {2005},
  isbn        = {3-540-25593-1},
}