Innovative education at postgraduate level: Flipped classroom Pilar Moreno-Crespo, Celia Corchuelo-Fernández, Aránzazu Cejudo-Cortés and Coral I. Hunt-Gómez SHS Web Conf., 66 (2019) 01033 Published online: 14 August 2019 DOI: 10.1051/shsconf/20196601033