question: What is the name of the person whose music was influenced by An Outdoor Overture and Billy the Kid?
context: In April 1939 Britten and Pears sailed to North America, going first to Canada and then to New York. They had several reasons for leaving England, including the difficult position of pacifists in an increasingly bellicose Europe; the success that Frank Bridge had enjoyed in the US; the departure of Auden and his friend Christopher Isherwood to the US from England three months previously; hostile or belittling reviews of Britten's music in the English press; and under-rehearsed and inadequate performances. Britten and Pears consummated their relationship and from then until Britten's death they were partners in both their professional and personal lives. When the Second World War began, Britten and Pears turned for advice to the British embassy in Washington and were told that they should remain in the US as artistic ambassadors. Pears was inclined to disregard the advice and go back to England; Britten also felt the urge to return, but accepted the embassy's counsel and persuaded Pears to do the same.Already a friend of the composer Aaron Copland, Britten encountered his latest works Billy the Kid and An Outdoor Overture, both of which influenced his own music. In 1940 Britten composed Seven Sonnets of Michelangelo, the first of many song cycles for Pears. Britten's orchestral works from this period include the Violin Concerto and Sinfonia da Requiem. In 1941 Britten produced his first music drama, Paul Bunyan, an operetta, to a libretto by Auden. While in the US, Britten had his first encounter with Balinese gamelan music, through transcriptions for piano duo made by the Canadian composer Colin McPhee. The two met in the summer of 1939 and subsequently performed a number of McPhee's transcriptions for a recording. This musical encounter bore fruit in several Balinese-inspired works later in Britten's career.Moving to the US did not relieve Britten of the nuisance of hostile criticism: although Olin Downes, the doyen of New York music critics, and Irving Kolodin took to Britten's music, Virgil Thomson was, as the music scholar Suzanne Robinson puts it, consistently "severe and spiteful". Thomson described Les Illuminations (1940) as "little more than a series of bromidic and facile 'effects' ... pretentious, banal and utterly disappointing", and was equally unflattering about Pears's voice. Robinson surmises that Thomson was motivated by "a mixture of spite, national pride, and professional jealousy". Paul Bunyan met with wholesale critical disapproval, and the Sinfonia da Requiem (already rejected by its Japanese sponsors because of its overtly Christian nature) received a mixed reception when Barbirolli and the New York Philharmonic premiered it in March 1941. The reputation of the work was much enhanced when Koussevitzky took it up shortly afterwards.
answers.text: Britten