Financial Cryptography and Data Security. FC 2021 International Workshops : CoDecFin, Defi, VOTING, and WTSC, Virtual Event, March 5, 2021, Revised Selected Papers - Bernhard, Matthew; Bracciali, Andrea; Gudgeon, Lewis; Haines, Thomas; Klages-Mundt, Ariah; Matsuo, Shin'ichiro; Perez, Daniel; Sala, Massimiliano; Werner, Sam (Springer Berlin Heidelberg, 2021)