Metadata and Semantic Research 13th International Conference, MTSR 2019, Rome, Italy, October 28-31, 2019, Revised Selected Papers - Garoufallou, Emmanouel; Garoufallou, Emmanouel; Fallucchi, Francesca; Fallucchi, Francesca; William De Luca, Ernesto; William De Luca, Ernesto (Springer International Publishing : Imprint: Springer, 2019)