@inproceedings{Simpson_et_al_1997,
  title = "The Mechanical Verification of {S}olid {S}tate {I}nterlocking Geographic Data",
  author = "A. C. Simpson and J. C. P. Woodcock and J. W. Davies",
  year = "1997",
  booktitle = "Proceedings of Formal Methods Pacific, Wellington, New Zealand, 9--11 July",
  editor = "Groves, L. and Reeves, S.",
  pages = "223--242",
  publisher = "Springer-Verlag",
}