Letters from Prison

the help of G. Vittorio Amoretti, Alessandro Caprioglio, Giovanni Casale, Cesare Cases, Giuseppe Fiori, Piero Gerosa, Giacomo Porcelli, Salvatore Sechi, Paolo Spriano, and Vittorio Strada is acknowledged. Among the libraries where research was conducted, we are pleased to mention the Piero Gobetti Study Center in Turin. The philological help and suggestions of Carlo Pincin frequently facilitated and accelerated the work.