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On behalf of the Stadttheater Giessen and other clients, Herbert Gietzen rearranged a number of works for various instrumentations, including
John Psathas: Corybas
(from Piano Trio to large orchestra
Gregori Frid: Das Tagebuch der Anne Frank
(from solo piano to a chamber ensemble of 4 instruments)
Vincenzo Bellini: Zaira
(from large orchestra, corona conditioned, to a version for 13 instruments)