@misc{Beethoven_Ludwig_van_(1770-1827)_[01],
 author={Beethoven, Ludwig van (1770-1827)},
 howpublished={online},
 publisher={Éditions Heugel},
 title={[01] Quatuors a cordes : Op. 18. Vol. 1 (No 1-6)},
 type={druk muzyczny},
}