Bella Alten operatic career included six Metropolitan premiere performances – Adele in Die Fledermaus (1905), Gretel in Hänsel und Gretel (1905), Saffi in Der Zigeunerbaron (1906), Olga in Fedora (1906), Columbina in Le Donne Curiose (1912), and Lisetta in L'amore Medico (1914). In November 1905 when she sang Gretel in the premiere Metropolitan performance of Hänsel und Gretel, the composer Engelbert Humperdinck was in the audience. This opera received 11 performances that first season and was selected by Theodore Roosevelt's wife as a benefit for the Legal Aid Society. Alten sang Gretel in this opera every season she was with the Met
Monica Yunus Schwerin, where she also appeared as a last minute replacement in the role of Amor in "Orfeo ed Euridice". Yunus also won the Willam Matheus Sullivan Foundation Singer Award in 2003. In the 2004–2005 season, Yunus returned to Palm Beach Opera for their production of "Hänsel und Gretel" as Gretel. She also made her debuts at Anchorage Opera and the Spoleto Festival (USA) as Zerlina in Mozart's "Don Giovanni". Yunus also made her debut with Granite State Opera as Gilda in Verdi's "Rigoletto" and returned to Nashville Opera to perform the role of Adele in "Die Fledermaus". Yunus won the