The composer Friedrich Cerha has died at the age of 96. But what he left us is a complete “Lulu.”

When Alban Berg died unexpectedly – of blood poisoning from an insect bite on Christmas Eve, 1935 – his second opera remained incomplete. His work on “Lulu,” begun in 1929, was interrupted so that he could develop some of the music into a “Lulu Suite,” an attempt to subvert the Nazis, which had already added Berg to their catalogue of “entartete” – or degenerate – composers in 1933. When Erich Kleiber, who had introduced Berg’s first opera, “Wozzeck,” at the Berlin State Opera in 1925, performed the suite there in 1934, he was forced to resign and basically run out of the country.

Berg broke off work on the opera a second time to compose his Violin Concerto for Louis Krasner. This he dedicated to the memory of 18-year-old Manon Gropius, one of Berg’s muses, whom he and his wife had come to view as their own daughter. Manon’s birth parents were Alma Mahler, Gustav’s widow, and Walter Gropius. The concerto would go on to become Berg’s most beloved work.

At some point, the composer wrote to Anton Webern to let him know that “Lulu” was essentially complete. He anticipated he would need only two or three weeks to overhaul it before he started in on its orchestration.

After his death, it was found he had managed to complete most of it. The parts he did not were left in short score, with detailed indications as to his plans for filling out the orchestration.

Schoenberg, Webern, and Zemlinsky, all friends of Berg, declined to take up its completion. Berg’s widow was left with the impression that the task must have been impractical, if not impossible. It was only after her own death in 1976 that Friedrich Cerha moved ahead with plans to finish it.

“Lulu” received its premiere, incomplete, in Switzerland, in 1937. Cerha’s edition was first staged soon after its publication in 1979. This was rapturously received, and it is now the preferred version.

Lulu” has long since taken its place in the standard repertoire, alongside Berg’s “Wozzeck.”

Cerha himself produced orchestral music and five original operas. He was a teacher at Vienna’s University of Music and Performing Arts (formerly the Viennese Music Academy, where he studied). He received a doctorate in philosophy from the University of Vienna.

A noted interpreter of the music of the Second Viennese School (Schoenberg, Berg, and Webern), he was invited to conduct at orchestra halls, opera houses, and festivals around the world. He cofounded with his wife Gertraud and composer Kurt Schwertsik the contemporary music ensemble die reihe (“the row” or “the series”).

Interestingly, he and Gertraud were also founding members of the Joseph Marx Society. Though Marx is credited with having coined the term atonality, one would be hard-pressed to think of a 20th century composer more Romantic in outlook. The pianist Jorge Bolet described Marx’s “Romantic Piano Concerto” (1919-20) as his favorite among the great virtuoso works.

Of his own music, Cerha’s publisher singles out “Spiegel I-VII” as occupying a special place. His first opera, “Baal,” appeared in 1981.

Percussion Concerto (2007-08)

“Nachtstücke” (“Night Piece”) for piano trio (1992)

Spiegel II for 55 Strings (1964)

Act III of “Lulu”

Cerha talks about his music

Jorge Bolet performs Joseph Marx’s “Romantic Piano Concerto”