@article{sosym2008:davies,
  title = "Automatic Maintenance of Association Invariants",
  author = "James Welch and David Faitelson and Jim Davies",
  year = "2008",
  issn = "1619-1366",
  journal = "Software and Systems Modeling ",
  publisher = "Springer Berlin / Heidelberg",
  doi = "10.1007/s10270-008-0085-0",
}