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Nicolai Ghiaurov (or Nikolai Gjaurov, Nikolay Gyaurov, Bulgarian: Николай Гяуров) (September 13, 1929 – June 2, 2004) was a Bulgarian opera singer and one of the most famous basses of the postwar period. He was admired for his powerful, sumptuous voice, and was particularly associated with roles of Mussorgsky and Verdi. Ghiaurov married the Bulgarian pianist Zlatina Mishakova in 1956 and Italian soprano Mirella Freni in 1978, and the two singers frequently performed together. They lived in Modena until Ghiaurov's death in 2004 of a heart attack.