Dagmar de Corval Rybner Barclay (9 September 1890 - 22 July 1965) was a Swiss-German composer, pianist, and teacher who worked and corresponded with Sergei Rachmaninoff.
Cornelius changed the family name from “Rubner” to “Rybner.” Dagmar married the singer John Barclay.
She made her European debut as a pianist playing the Schumann piano concerto under conductor Felix Mottl.
[10][11][6][12] Rybner worked as Rachmaninoff’s assistant[4] and taught at Barnard College, Columbia University and the Curtis Institute of Music.
[14] Rybner’s works were published by Breitkopf & Hartel, Carl Fischer Music, Oliver Ditson, Luckhardt & Belder, and G. Schirmer Inc.[1][15][16][17] They include: