@inproceedings{ kacheck,
    author = "Christian Grothoff and Jens Palsberg and Jan Vitek",
    title = "Encapsulating Objects with Confined Types",
    booktitle = "Proceedings of the 16th {ACM SIGPLAN} conference on Object-oriented programing, systems, languages, and applications",
    pages = "241--253",
    publisher = "ACM SIGPLAN",
    url = "http://www.ovmj.org/kacheck/oopsla2001.ps",
    year = "2001"
}