Thematic Catalogue of the Works of Carl Philipp Emanuel Bach, E. Eugene Helm
Información encontrada
(539. Quartetto fürs Clavier, Flöte, Bratsche und Bass. 1788 (NV 52) W. 95. Aut. ms. bore marks of articulation for cello in the bass line of the keyboard part. In 1788 a separate "bass" part and a completely written-out keyboard part would probably have been the reason for classifying the work as a quartet rather than as a trio sonata)
