AI approaches to the complexity of legal systems XI-XII AICOL International Workshops 2018 and 2020: AICOL-XI@JURIX 2018, AICOL-XII@JURIX 2020, XAILA@JURIX 2020 : revised selected papers - Rodríguez-Doncel, Victor 1978-; Palmirani, Monica; Araszkiewicz, Michał; Casanovas, Pompeu; Pagallo, Ugo; Sartor, Giovanni 1959- (Springer, 2021)