My understanding is that berio originally allowed IXb to be transcribed for Harle and Roth. However, in all the books I've read on/about Berio, he doesn't discuss this relationship. Even denies it and states that both the new versions of the sequenzas were for Claude. There are a couple of printed editions, one from the 80's, and a more recent one. Both are inaccurate. The multiphonic fingerings listed are incorrect. If you listen to the recordings of Claude, Christian and Arno they play a more accurate multiphonic that was to the agreement of Berio, not the one in the universal edition. Also these editions are lacking a few of the altissimo sections that the above mentioned artists also perform correctly.