Aron (1930–1932), makes use of Sprechstimme String Quartet No. 4, op. 37 (1936). Fourth movement (Allegro), bars 882–888, all four instruments play col legno battuto, col legno tratto, and col legno tratto ponticello, on single notes and in double stops, tremolo, and in harmonics . String Trio, op. 45 (1946). The violin and cello play col legno battuto; the violin plays col legno tratto in double stops; all the instruments play col legno tratto ponticello, double stops; violin and viola play col legno tratto ponticello in double stops, which are also played tremolo (; ) Igor Stravinsky The Firebird, the strings occasionally play col legno, striking the wood of their bows on the strings Heitor Villa-Lobos Assobio a játo (1950), requires the flute to play "imitando fischi in toni ascendenti" (imitating whistles in rising tones), accomplished by blowing into the embouchure "as if one were warming up the instrument on a cold day" . Chôros No. 8 (1925), for orchestra and two pianos, requires one or both of the pianos to insert paper between the strings for a passage . References External links Carlo Forlivesi Official Website Panayiotis Kokoras' home page Extended techniques