In GC, FE and EE1 (→EE2) there is no returning a2. This patent inaccuracy was corrected in GE and EE3.
Compare the passage in the sources »
category imprint: Interpretations within context; Differences between sources
issues: EE revisions, Errors in FE, Errors in EE, Omissions to cancel alteration, GE revisions, Errors of GC
notation: Pitch