Question: Who is the spouse of the Russian composer that created the music for the ballet the firebird?

full_context: Document 1: The Firebird: The Firebird (; ) is a ballet and orchestral concert work by the Russian composer Igor Stravinsky. It was written for the 1910 Paris season of Sergei Diaghilev's Ballets Russes company; the original choreography was by Michel Fokine, with a scenario by Alexandre Benois and Fokine based on the Russian fairy tales of the Firebird and the blessing and curse it possesses for its owner. When first performed at the Opéra de Paris on 25 June 1910, the work was an instant success with both audience and critics.
Document 2: Anna Pavlova: Anna Pavlovna (Matveyevna) Pavlova (Russian: Анна Павловна (Матвеевна) Павлова; February 12 (O.S. January 31) 1881 -- January 23, 1931) was a Russian prima ballerina of the late 19th and the early 20th centuries. She was a principal artist of the Imperial Russian Ballet and the Ballets Russes of Sergei Diaghilev. Pavlova is most recognized for the creation of the role The Dying Swan and, with her own company, became the first ballerina to tour ballet around the world.
Document 3: Vera de Bosset: Vera de Bosset Stravinsky (January 7, 1889 – September 17, 1982) was a Russian-born American dancer and artist. She is better known as the mistress and, ultimately, second wife of the Russian composer Igor Stravinsky, who married her in 1940.
Document 4: The Firebird: The Firebird (French: L'Oiseau de feu; Russian: Жар - птица, translit. Zhar - ptitsa) is a ballet and orchestral concert work by the Russian composer Igor Stravinsky. It was written for the 1910 Paris season of Sergei Diaghilev's Ballets Russes company; the original choreography was by Michel Fokine, with a scenario by Alexandre Benois and Fokine based on the Russian fairy tales of the Firebird and the blessing and curse it possesses for its owner. When first performed at the Opéra de Paris on 25 June 1910, the work was an instant success with both audience and critics.
Document 5: Violette Verdy: Violette Verdy (born Nelly Armande Guillerm; 1 December 1933 – 8 February 2016) was a French ballerina, choreographer, teacher, and writer who worked as a dance company director with the Paris Opera Ballet in France and the Boston Ballet in the United States. From 1958 to 1977 she was a principal dancer with the New York City Ballet where she performed in the world premieres of several works created specifically for her by choreographers George Balanchine and Jerome Robbins. She was Distinguished Professor of Music (Ballet) at the Jacobs School of Music, Indiana University, in Bloomington, and the recipient of two medals from the French government.
Document 6: Stravinsky Inlet: Stravinsky Inlet () is an ice-covered inlet lying between Shostakovich Peninsula and Monteverdi Peninsula in southern Alexander Island, Antarctica. The inlet was first mapped by Directorate of Overseas Surveys from satellite imagery supplied by U.S. National Aeronautics and Space Administration in cooperation with U.S. Geological Survey. Named by United Kingdom Antarctic Place-Names Committee after Igor Stravinsky (1882–1971), Russian-born composer who became a French citizen, ultimately a citizen of the United States.
Document 7: Flight of the Bumblebee: ``Flight of the Bumblebee ''is an orchestral interlude written by Nikolai Rimsky Korsakov for his opera The Tale of Tsar Saltan, composed in 1899 -- 1900. Its composition is intended to musically evoke the seemingly chaotic and rapidly changing flying pattern of a bumblebee. Despite the piece's being a rather incidental part of the opera, it is today one of the more familiar classical works because of its frequent use in popular culture.
Document 8: Nicolas Zverev: He studied at the Moscow ballet class at the theatre school of the Moscow Imperial troupe. In 1912 he was invited by Sergei Diaghilev to his troupe Ballets russes. Zverev participated in the Ballets russes from 1912 or 1913 to 1926. Among his roles were Slave ("Scheherazade", Michel Fokine’s ballet), Cossack Chief (La Boutique fantasque, 1919), one of the men (Les biches, 1924) etc.
Document 9: Flight of the Bumblebee: ``Flight of the Bumblebee ''is an orchestral interlude written by Nikolai Rimsky - Korsakov for his opera The Tale of Tsar Saltan, composed in 1899 -- 1900. Its composition is intended to musically evoke the seemingly chaotic and rapidly changing flying pattern of a bumblebee. Despite the piece's being a rather incidental part of the opera, it is today one of the more familiar classical works because of its frequent use in popular culture.
Document 10: Rusalka (Dargomyzhsky): Rusalka () is an opera in four acts, six tableaux, by Alexander Dargomyzhsky, composed during 1848-1855. The Russian libretto was adapted by the composer from Pushkin's incomplete dramatic poem of the same name. It premiered on 4 May 1856 (Old Style) at the Theatre-circus, conducted by Konstantin Lyadov (father of Anatoly Lyadov), choreographed by Marius Petipa and Nikolay Goltz, but was badly received predominantly by the aristocracy.
Document 11: Irina Kolpakova: In the 1990s she worked for several seasons as choreographer and coach at the American Ballet Theatre in New York City. She is currently a professor of classical dance at the Vaganova Academy of Russian Ballet in St. Petersburg and a ballet coach at American Ballet Theatre.
Document 12: Frédéric Chopin: Chopin's music was used in the 1909 ballet Chopiniana, choreographed by Michel Fokine and orchestrated by Alexander Glazunov. Sergei Diaghilev commissioned additional orchestrations—from Stravinsky, Anatoly Lyadov, Sergei Taneyev and Nikolai Tcherepnin—for later productions, which used the title Les Sylphides.
Document 13: Kseniya Boguslavskaya: Born in St. Petersburg, she studied art in Paris from 1911 to 1913. She returned to St. Petersburg in 1913 and married Ivan Puni. Their apartment in St Petersburg became a meeting place for avant-garde artists and poets. With Puni she published the cubo-futurist booklet "Roaring Parnassus" («Рыкающий Парнас») in 1914.
Document 14: Portrait of Yevgeny Mravinsky: Portrait of Yevgeny Mravinsky is a painting by Russian portrait artist Lev Russov (1926–1987), whose work depicts the famous Russian and Soviet musician Yevgeny Aleksandrovich Mravinsky (1903—1988), principal conductor of the Leningrad Philharmonic Orchestra in 1938–1988 years.
Document 15: The Fountain of Bakhchisarai (ballet): The Fountain of Bakhchisarai (Russian: Бахчисарайский фонтан) is a full-length ballet in four acts, choreographed by Rostislav Zakharov to music by Boris Asafyev. The libretto by Nikolai Volkov is based on the 1823 poem of the same title by Alexander Pushkin. The ballet premiered on 28 September 1934 at the Kirov Academic Theatre of Opera and Ballet, with Galina Ulanova as Maria, Olga Iordan as Zarema, Mikhail Dudko as Khan Girey, and Konstantin Sergeyev as Vaslav.
ground_truth: Vera de Bosset
sub_queries: russian composer created the music for the ballet the firebird Answer: Igor Stravinsky
Igor Stravinsky >> spouse Answer: Vera de Bosset