RIAS report on an interview with Jiri Hájek, co-signer of the "Charta 77" (1968 Czech foreign minister), 31 March 1977 (in German) (Source: Archiv Deutschlandradio, Broadcast: Rundschau am Abend, Moderator/Reporter: Willi Knecht, Dieck Werkiek (Holländischer Rundfunk))