Task: Question Answering
Input (English): Passage: Throughout the early years of the July Monarchy, Alkan continued to teach and play at public concerts and in eminent social circles. He became a friend of many who were active in the world of the arts in Paris, including Franz Liszt (who had been based there since 1827), George Sand, and Victor Hugo. It is not clear exactly when he first met Frédéric Chopin, who arrived in Paris in September 1831. In 1832 Alkan took the solo role in his first Concerto da camera for piano and strings at the Conservatoire. In the same year, aged 19, he was elected to the influential Société Académique des Enfants d'Apollon (Society of the Children of Apollo), whose members included Luigi Cherubini, Fromental Halévy, the conductor François Habeneck, and Liszt, who had been elected in 1824 at the age of twelve. Between 1833 and 1836 Alkan participated at many of the Society's concerts. Alkan twice competed unsuccessfully for the Prix de Rome, in 1832 and again in 1834; the cantatas which he wrote for the competition, Hermann et Ketty and L'Entrée en loge, have remained unpublished and unperformed.In 1834 Alkan began his friendship with the Spanish musician Santiago Masarnau, which was to result in an extended and often intimate correspondence which only came to light in 2009. Like virtually all of Alkan's correspondence, this exchange is now one-sided; all of his papers (including his manuscripts and his extensive library) were either destroyed by Alkan himself, as is clear from his will, or became lost after his death. Later in 1834 Alkan made a visit to England, where he gave recitals and where the second Concerto da camera was performed in Bath by its dedicatee Henry Ibbot Field; it was published in London together with some solo piano pieces. A letter to Masarnau and a notice in a French journal that Alkan played in London with Moscheles and Cramer, indicate that he returned to England in 1835. Later that year, Alkan, having found a place of retreat at Piscop outside Paris, completed his first truly original works for solo piano, the Twelve Caprices, published in 1837 as Opp. 12, 13, 15 and 16. Op. 16, the Trois scherzi de bravoure, is dedicated to Masarnau. In January 1836, Liszt recommended Alkan for the post of Professor at the Geneva Conservatoire, which Alkan declined, and in 1837 he wrote an enthusiastic review of Alkan's Op. 15 Caprices in the Revue et gazette musicale. 
Question: Who completed the Twelve Caprices?
Output (English): Alkan.