An unfinished piece of music by Wolfgang Amadeus Mozart has been played, possibly for the first time, after a relative decided to auction off the work composed about 200 years ago. Five students at London's Royal College of Music on Thursday performed the 35 bars of the "Quintet in B Flat Major" for piano and wind instruments, oboe, clarinet, basset horn and bassoon. "They are an unusual group of instruments and I think the work might not have been completed because Mozart may have found it difficult to find musicians to play them," said Stephen Roe, director of manuscripts at Sotheby's. The firm will auction the music Nov. 21. The fragment took 1 1/4 minutes to perform and sounded complete, although it was only the opening of a work. Roe said the single sheet of music was on the same kind of paper Mozart was using in 1783.