@Article {dfjlps-vldb2018,
    author = {S. {De Capitani di Vimercati} and S. Foresti and S.
Jajodia and G. Livraga and S. Paraboschi and P.
Samarati},
    title = {An Authorization Model for Multi-Provider Queries},
    journal = {Proc. of the VLDB Endowment},
    volume = {11},
    number = {3},
    month = {November},
    year = {2017}
}