The version of GC (→GE1) is certainly erroneous – the double stroke of the same note (a1) by the L.H., unjustified by the voice leading, does not make any sense, as far as the piano technique is concerned. It is worth observing that the copyist initially wrote a chord within the correct, one octave, span, yet with a double Terzverschreibung error – a-c1-e1-a1. He then corrected it, yet only partially.
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category imprint: Differences between sources
issues: Terzverschreibung error, GE revisions, Errors of GC, Alterations in GC
notation: Pitch