@InProceedings {cs.st92,
    author = {S. Castano and P. Samarati},
    booktitle = {Proc. of the IEEE 26th Int. Carnahan Conf. on Security Technology},
    title = {An Object-Oriented Security Model for Office Environments},
    address = {Atlanta},
    pages = {146-152},
    month = {October},
    year = {1992}
}