Demanding tour schedules caused Rachmaninoff's composition output to slow significantly; between his arrival to the US in 1918 and his death, he completed just six compositions barring some revisions to previous works and piano transcriptions for his concert repertoire. The composer later admitted that by leaving Russia, "I left behind my desire to compose: losing my country, I lost myself also". In 1926, after concentrating on touring for the past eight years, he took a year's break from performing and completed the first two of his last six pieces, the Piano Concerto No. 4, which he had started in 1917, and "Three Russian Songs" which he dedicated to Leopold Stokowski. Rachmaninoff sought the company of fellow Russian musicians and befriended pianist Vladimir Horowitz in 1928. The men remained supportive of each other's work, each making a point of attending concerts given by the other. Horowitz remained a champion of Rachmaninoff's solo works and his Piano Concerto No. 3, about which Rachmaninoff remarked publicly after a performance in 1942: "This is the way I always dreamed my concerto should be played, but I never expected to hear it that way on Earth." In 1930, in a rare occurrence, Rachmaninoff allowed Italian composer Ottorino Respighi to orchestrate pieces from his "Études-Tableaux", Op. 33 (1911) and the "Études-Tableaux", Op. 39 (1917), giving Respighi the inspirations behind the compositions.