Emma Nevada (née Wixom) (7 February 1859 – 20 June 1940) was an American operatic soprano particularly known for her performances in operas by Bellini and Donizetti and the French composers Ambroise Thomas, Charles Gounod, and Léo Delibes.
 Considered one of the finest coloratura sopranos of the late 19th and early 20th centuries, her most famous roles were Amina in "La sonnambula", and the title roles in "Lakmé", "Mignon", "Mireille", and "Lucia di Lammermoor.
Igor Fyodorovich Stravinsky (sometimes spelled "Strawinski", "Strawinsky", or "Stravinskii"; Ukrainian: І́гор Фе́дорович Страві́нський , ] ;Russian: И́горь Фёдорович Страви́нский , "Igorʹ Fëdorovič Stravinskij"; ] ; 17 June [O.S. 5 June] 1882 6 April 1971) was a Russian Empire-born composer, pianist, and conductor.
 He is widely considered one of the most important and influential composers of the 20th century.
This is list of operas and operettas written by the French composer Léo Delibes (1836–1891).
His first commercial recording was the complete piano solo works of Igor Stravinsky.
 Since then he has recorded music by Alexander Scriabin, Robert Schumann and Olivier Messiaen, the piano part of Igor Stravinsky's "Petrushka" with the New Philharmonia under Erich Leinsdorf, and Béla Bartók's "Music for Strings, Percussion and Celesta" with Sir Georg Solti and the London Symphony Orchestra.
 He has completed a cycle of recordings devoted to the entire piano music of Enrique Granados.
 Subsequently he undertook to record Franz Liszt's 12 "Transcendental Etudes" and "12 Etudes", Op. 1.
 Rajna has often performed his own two piano concertos.
Le roi l'a dit ("The King Has Spoken") is an opéra comique in three acts by Léo Delibes to a French libretto by Edmond Gondinet.
 It is a lively comedy, remarkably requiring 14 singers – six men and eight women.
 The libretto had first been offered in 1871 to Offenbach; the title also went through various permutations ("Le Talon rouge", "Si le Roi le savait", "Le Roi le sait") before settling on its final name.
 The 1885 revival brought further modifications to the libretto.
Scherzo fantastique, op. 3, composed in 1908, is the second orchestral work by Igor Stravinsky (preceded by the Symphony in E-flat).
 It was inspired by Maurice Maeterlinck's 1901 essay "La Vie des Abeilles" (The Life of Bees), which Stravinsky and his wife Catherine Nossenko read in 1907.
 Ten years later, Léo Staats adapted it as a ballet for the Opéra Garnier, with the title "Les Abeilles".
"La source (The Spring)" is a ballet in three acts/four scenes with a score composed by Léo Delibes and Ludwig Minkus (Minkus: Act I & Act III-Scene 2/Delibes: Act II & Act III-Scene 1) which was premiered in 1866 with choreography by Arthur Saint-Léon.
 In 1878 in Vienna it was called "Naïla, die Quellenfee" ("Naïla, the Waternymph").
Clément Philibert Léo Delibes (] ; 21 February 1836 – 16 January 1891) was a French composer of the Romantic era (1815–1910), who specialised in ballets, operas, and other works for the stage.
 His most notable works include the ballets "Coppélia" (1870) and "Sylvia" (1876), as well as the operas "Le roi l'a dit" (1873) and "Lakmé" (1883).
This is a list of ballets by Léo Delibes (1836–1891).
Balanchine's had previously made a "pas de deux" to music from Léo Delibes' "Sylvia" in 1950; he expanded this into a divertissement in 1965.
 The final version uses music from Delibes' ballets "La source" and "Sylvia" and choreography from the earlier pas de deux and divertissement.

Question: Léo Delibes and Igor Stravinsky, both had which musical occupation?
Answer: composer