‚The word Lullaby is used in the sense of an incantation to sleep' explains Oliver Knussen in a programme note for his exquisite 6-minute piano piece Sonya's Lullaby. ‚Sonya is my daughter, who was a four-month-old insomniac in October 1977 when the first sketch of this piece was written.  Formally the music is, I hope, self-explanatory - but perhaps it is worth mentioning that an initials stimulus toward the piano writing was the harmonic exploitation of overtones produced from the lowest register of the instrument by composers as diverse as Brahms, Scriabin, Copland and Carter.'  Sonya's Lullaby forms the central panel of Knussen's triptych of chamber works which also includes Autumnal for violin and piano, and Cantata for oboe and string trio.