Shifting Polarization and Twitter News Influencers between two U.S. Presidential Elections. - James Flamino; Alessandro Galezzi; Stuart I. Feldman; Michael W. Macy; Brendan Cross; Zhenkun Zhou; Matteo Serafino; Alexandre Bovet; Hernán A. Makse; Boleslaw K. Szymanski (CoRR, 2021)