From www.mutopiaproject.org

The Fugue for String Quintet in D major, Op. 137, was composed by Ludwig van Beethoven. It was composed in 1817, and was the only work he completed for string quintet in his late period. After Beethoven's death in 1827, Breitkopf & Härtel published the work, hence the high opus number. The composition is scored for a string quintet with two violas.
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