Gallimathias musicum

 in D major, K. 32, is a quodlibet composed in March 1766 by Wolfgang Amadeus Mozart during his grand tour of Europe. It was first performed at The Hague on 11 March 1766. 
A typical performance of this piece lasts twenty minutes.
Instrumentation and structure.
The work is scored for strings, two horns, two oboes, bassoon and harpsichord and consists of seventeen movements:
Sources of the music.
The piece has some movements which were composed on the basis of other existing pieces not by Mozart.
Manuscripts.
"Galimathias musicum" survives in four manuscripts which represent two different versions of the work.