After the first edition of this book [LIT. 10] was in final proofs, we heard about a recently published book [LIT. 9], "Research on Weiqi Fayanglun", by Cheng. As far as we can see, for problem 120, the author's main results of interest to us are: He ...

• assumes that a Black prisoner has been captured before the problem starts (#1; 771) /
  (#2; 778),
• uses the second throw-in at lower right (#1; 768) / (#2; 788),
• uses the "late", decisive oki at lower right (#1; 769) / (#2; 781),
• starts the endgame on the left side before further occupying Black's liberties at top right ( 767),
• gives the final result as jigo,
• does not mention the guzumi at top right,
• does not mention the hasami-tsuke at top right,
• and does not mention the tsuke at top left.