The Piano Sonata in B-flat major, K. 498a (Anh. 136), is a piano sonata in four movements. It was first printed in 1798 by P. J. Thonus in Leipzig on behalf of Breitkopf & Härtel and attributed to Wolfgang Amadeus Mozart; an edition printed in c. 1805 already credited it as opus 26 of the Thomascantor August Eberhard Müller (1767–1817).[1] Some publications still attribute it to Mozart, often as Piano Sonata No. 20.[2]
A typical performance lasts for about 19 minutes. The movements are:
The musicologist Alfred Einstein suggested that the Menuetto from this work might be a piano arrangement of the "missing movement" of Mozart's Eine kleine Nachtmusik, K. 525 (1787).[3]
The Andante is an arrangement of the variations movement of the concerto K. 450 in B-flat major, and the Rondo incorporates arrangements of passages from the finales of the B-flat concerti K. 450, K. 456, and K. 595.
. Alfred Einstein. Mozart: His Character, His Work. Arthur Mendel. Nathan Broder. 207. 1965. Oxford University Press. 31827291. New York. 978-0-19-500732-9. registration.
