In the earlier part of the 20th century, more composers began to write for the viola, encouraged by the emergence of specialized soloists such as Lionel Tertis. Englishmen Arthur Bliss, York Bowen, Benjamin Dale, and Ralph Vaughan Williams all wrote chamber and concert works for Tertis. William Walton, Bohuslav Martinů, and Béla Bartók wrote well-known viola concertos. Paul Hindemith wrote a substantial amount of music for the viola; being himself a violist, he often performed his own works. Claude Debussy's Sonata for flute, viola and harp has inspired a significant number of other composers to write for this combination.