Question: Who commissioned the 1919 ballet written by the creator of the role of the Can-Can Dancer in "La Boutique fantasque"?

Related documents: [0]  [DOC] Leonid Fyodorovich Myasin (Russian: Леони́д Фёдорович Мя́син ), better known in the West by the French transliteration as Léonide Massine (9 August [O.S. 28 July] 1896 15 March 1979), was a Russian choreographer and ballet dancer. Massine created the world's first symphonic ballet, "Les Présages", and many others in the same vein. Besides his "symphonic ballets," Massine choreographed many other popular works during his long career, some of which were serious and dramatic, and others lighthearted and romantic. He created some of his most famous roles in his own comic works, among them the Can-Can Dancer in "La Boutique fantasque" (1919), the Hussar in "Le Beau Danube" (1924), and, perhaps best known of all, the Peruvian in "Gaîté Parisienne" (1938). [END] 
[1]  [DOC] El sombrero de tres picos ("The Three-Cornered Hat" or "Le tricorne") is a ballet choreographed by Léonide Massine to music by Manuel de Falla, commissioned by Sergei Diaghilev and premiered complete in 1919. It is not only a ballet with Spanish setting but one that also employs the techniques of Spanish dance (adapted and somewhat simplified) instead of classical ballet. [END]  
Answer: Sergei Diaghilev
Sergei Diaghilev