Paris, she played Liszt, Chopin, and Mozart and received her first press reviews. From twelve to fifteen years of age, she performed in a number of different cities, including Paris, where Camille Saint-Saëns is said to have remarked of her, "I have just heard the best pianist in the world." At age fifteen, she was sent to study in Paris. She had lessons from Vincent d’Indy in harmony and fugue, studied piano with Alfred Cortot, and learned harmony from Nadia Boulanger. The latter helped her to prepare for the Prix de Rome, although it is unclear whether she actually entered the competition formally, and taught her some composition techniques. She toured the capitals of Europe when she was sixteen, and accompanied the dancer Vincente Escuderro in Madrid. It was there that she became keenly interested in Spanish folklore. She was offered the opportunity to become an official musician at the Spanish royal court, but her parents sent her back to Paris instead for further study. Her concert career was interrupted in 1921, on the eve of a United States tour, by a bout of ill health and what the French call "le trac", or an attack of nerves. Her diffidence and stage fright were to follow her throughout her career as a composer. She became desperately shy when she had to show Piaf a new song, even after years of collaboration. Almost every person who knew Monnot and who later wrote about her has drawn attention to her shyness and absent-mindedness. Her second vocation, songwriting, was just a pastime at first. A fan of popular music on the radio in the early 1920s, including jazz and dance music, she began writing songs because a family friend encouraged her to write a waltz for a film based on a play by Tristan Bernard. This song, written with Bernard in 1931, was entitled "Ah! les mots d’amour!" and sung by Jane Marny. The lyricist Marc Hély then asked her to compose the music for "Viens dans mes bras", sung by Lucienne Boyer and published by Salabert. Her talent was quickly recognized, and she was encouraged to continue. She persevered, and in 1935, the song "L’Étranger" was born out of her collaboration with the journalist-lyricist Robert Malleron and the accordionist-composer Robert Juel, who co-authored the music. The song was awarded the Grand Prix de l'Académie Charles Cros that year. The Piaf years "L'Étranger"