an Entity references as follows:
Fidelio / Beethoven, comp.; Helga Dernesch, S (Leonore); Jon Vickers, T (Florestan); Karl Ridderbusch, B (Rocco); Zoltan Kélémen, B (Don Pizzaro)... [et al.]; Chor der Deutschen Oper Berlin; Walter Hagen Groll, chef de choeur; Berliner Philharmoniker; Herbert von Karajan, dir.