Mildred Cooper

Mildred Couper (born Mildred Cooper) was an Argentine-American composer, pianist, teacher, and music theorist known for early experiments in quarter-tone and other microtonal music. Born in Buenos Aires, she studied in Europe, later taught and worked in New York, and eventually settled in Santa Barbara, California, where she continued her musical career.

Buenos Aires, Argentina Dec 10, 1887 Wikipedia
classical microtonal quarter-tone