Trapping of Magnetic Flux in Bi-2223 Ceramic Superconductors Doped with α-Al2O3 Nanoparticles - Hernández-Wolpez, M; Gallart-Tauler, P R; Garcia Fornaris, I; Govea-Alcaide, E; Perez-Tijerina, E; Jardim, Renato de Figueiredo; Muné, Pedro (Journal of Superconductivity and Novel Magnetism, 2019)