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In page Nell Rankin:

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She appeared at the Teatro Colón, Bellas Artes Opera in Mexico City, the Liceu in Barcelona and a score of other companies in Europe and North America. She was an admired recitalist and concert singer throughout her career. She was asked often asked by Sir Rudolf Bing to look soprano roles such as Elsa in Lohengrin. "Mr. Bing, I AM as soprano, but I am a MEZZO soprano." This is advice she would also give her students. After she retired from the Metropolitan Opera, Rankin devoted herself to teaching, first at the Academy of Vocal Arts in Philadelphia, from 1977 to 1984. Among her students were Tenor Richard Burke, Bass-Baritone Lucas Ernst, and Mezzo-Soprano Wanda Brister. She taught privately in New York City until she retired in 1991.[citation needed]