A Dictionary of Music and Musicians/Hammerklavier
HAMMERKLAVIER, i. e. Pianoforte. Beethoven's Sonata, op. 106, composed 1816–7, was superscribed by him 'Grosse Sonate fur das Hammerklavier.' So is op. 101, only at that time the German fit was not so strongly on Beethoven, and he gives the Italian name as well. By op. 109 he has returned to the Italian name alone.
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