Informazzjoni minn organizzazzjoni tal-arti (Verifikat minn Operabase)
Fourth Chamber Concert – Members of Kölner Rundfunk-Sinfonieorchester (WDR) by Stockhausen, Webern, Boulez, Minn (1960/1960), Surmast Direttur Pierre Boulez, Stiftung Mozarteum, Salzburg, Austria