Ludwig van Beethoven composed his Piano Trio in B flat major, Op. 11, in 1797. It was published in Vienna the following year, dedicated to Countess Maria Wilhelmine von Thun, as part of a series of early chamber works involving woodwind instruments. The trio is scored for piano, clarinet, and cello, the later two being replaceable by violin and bassoon respectively. The work is sometimes referred to as the "Gassenhauer Trio", because its third movement includes nine variations from a very popular tune at the time (a 'Gassenhauer'), which originated from a dramma giocoso by Joseph Weigl. This trio is usually left out of the ordinal numbering of Beethoven's piano trios, because of its unusual instrumentation.