an Entity references as follows:
Doris Soffel first played the violin, then switched to singing at the Hochschule für Musik und Theater München. She was member of the Stuttgart Opera ensemble from 1973 to 1982. Her international breakthrough was as Sesto in Mozart's La clemenza di Tito at the Royal Opera House, London in 1982. She sang Fricka in the Bayreuth Festival 1983 and was the only German coloratura mezzo with an international career, singing in works by Gioachino Rossini, Gaetano Donizetti, and Vincenzo Bellini. She sang world premieres by contemporary composers like Aribert Reimann and Krysztof Penderecki and had performances worldwide of Gustav Mahler's vocal works. From 1994, more dramatic roles like Judith in Béla Bartók's "Bluebeard's Castle", Eboli in Verdi's Don Carlo and Amneris in his Aïda. Since 1999 she