As a regular and happy visitor of Sheet Music Archives, I would like to make here some observations that could be useful for you and other music lovers: Here is the solution for Mozart's "mystery sonata". I got it on page # 1031 of the excellent biography "Wolfgang Amadeus Mozart" written (in french) by Jean and Brigitte Masson and published in 1990 by the "Librairie Arth�me Fayard" in Paris. I ignore if there is somewhere an english version available. This "sonata" is , in fact, not a complete and official Mozart sonata.. The "Allegro", probably composed in 1786, is now numbered " k 498a - Allegro in B flat for piano". The "Minuet" could be, according to Alfred Einstein, a transposition of the - unfortunately lost - Minuet and Trio initially ment for "A Little Night Music" k 525. The remaining "Andante" and "Finale", simply appear to be transpositions of some movements of Mozart's Piano Concertos # 15, 18 and 27 ! Published by Andr� during the year 1798 , thus a long time after Mozart's death, this "sonata", defined as "Opus LXII # 2" !!!!, has only to be seen as a commercial stunt, probably ment to improve Constance's precarious financial situation. --from P. Nuis