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In page Stefania Turkewich:

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Turkewich's opera Oksana's Heart was performed in Winnipeg in 1970 at the Centennial Concert Hall, under the artistic direction of her sister Irena Turkevycz-Martynec.[1] She continued to compose through the 1970s.[citation needed] She died on 8 April 1977, aged 78, in Cambridge.[2]