The semantic web 15th International Conference, ESWC 2018, Heraklion, Crete, Greece, June 3–7, 2018 : proceedings - Gangemi, Aldo; Navigli, Roberto; Vidal, María-Esther; Hitzler, Pascal; Troncy, Raphael; Hollink, Laura; Tordai, Anna; Alam, Mehwish (Springer, 2018)