 In Italian scores up to Gioachino Rossini's Overture to "William Tell", the cor anglais was written in bass clef an octave lower than sounding.The unmodified bass clef is so common that performers of instruments and voice parts whose ranges lie below the stave simply learn the number of ledger lines for each note through common use, and if a line's true notes lie significantly above the bass clef the composer or publisher will often simply write the part in either the treble clef or notated an octave down under an "8va" bracket.Use of octave-marked clefs appears to have increased as computers have become more important in musical transcription.