Sextet was by the Polish composer who has completed how many operas?
Krzysztof Penderecki Krzysztof Eugeniusz Penderecki ( ; ] ; born 23 November 1933) is a Polish composer and conductor. "The Guardian" has called him Poland's greatest living composer. Among his best known works are his "Threnody to the Victims of Hiroshima", "Symphony No. 3", "St. Luke Passion", "Polish Requiem", "Anaklasis", "Utrenja", four operas, eight symphonies and other orchestral pieces, a variety of instrumental concertos, choral settings of mainly religious texts, as well as chamber and instrumental works.
Prince Igor Prince Igor (Russian: Князь Игорь , "Knyaz' Igor'") is an opera in four acts with a prologue, written and composed by Alexander Borodin. The composer adapted the libretto from the Ancient Russian epic "The Lay of Igor's Host", which recounts the campaign of Rus' prince Igor Svyatoslavich against the invading Cuman ("Polovtsian") tribes in 1185. He also incorporated material drawn from two medieval Kievan chronicles. The opera was left unfinished upon the composer's death in 1887 and was edited and completed by Nikolai Rimsky-Korsakov and Alexander Glazunov. It was first performed in St. Petersburg, Russia, in 1890.