@techreport{RR-04-23,
  title = "Safety is not a restriction at level 2 for string languages",
  author = "K. Aehlig and J. G. de Miranda and C.-H. L. Ong",
  year = "2004",
  institution = "Oxford University Computing Laboratory",
  month = "October",
  number = "RR-04-23",
}