@InProceedings {bbfs.vldb96,
    author = {E. Bertino and C. Bettini and E. Ferrari and P. Samarati},
    booktitle = {Proc. of the 22nd International Conference on Very Large Databases (VLBD)},
    title = {Supporting Periodic Authorizations and Temporal Reasoning in Database Access Control},
    address = {Bombay, India},
    month = {September},
    year = {1996}
}