 <unk> <unk> ( September 20 , 1885 – December 20 , 1958 ) was a Canadian @-@ American <unk> @-@ soprano and voice teacher . She performed and popularised songs by contemporary composers throughout her career and sang in the American premieres of several works by Erik <unk> , Maurice Ravel and Igor Stravinsky , including the title role in the latter 's <unk> . 
