@book{VDM08,

    author    = "Cai-Nicolas Ziegler",
    title     = "Towards Decentralized Recommender Systems",
    publisher = "Verlag Dr. Müller",
    year      = "2008",
    month     = "May",
    isbn      = "ISBN 363901149X",
    address   = "Saarbrücken, Germany"
}