@InProceedings {ddps-p2p2004,
    author = {E. Damiani and S. {De Capitani di Vimercati} and S. Paraboschi and P. Samarati},
    booktitle = {Proc. of the fourth IEEE International Conference on Peer-to-Peer Computing},
    title = {{P2P}-based Collaborative Spam Detection and Filtering},
    address = {Zurich, Switzerland},
    month = {August},
    day = {25-27},
    year = {2004}
}