The Cambridge History of English and American Literature in 18 Volumes (1907–21).
Volume IV. Prose and Poetry: Sir Thomas North to Michael Drayton.
§ 6. Lack of evidence making Shakespeare responsible for Corrections or Additions
Some critics have held that Shakespeare was responsible for corrections and additions in the folio text of these plays. This assumption leaves out of account two important facts. In certain cases, it is unquestionably the quarto text which has been altered, and which has received additions. Moreover, it is obvious that these changes could not have been made for stage purposes. They must, therefore, have been made with a view to printing the plays; but it is surely inconceivable that Shakespeare should have made these minute corrections without also authorising an edition of the revised plays.