Thank you all for all the precious answers that I am receiving publicly and privately.
I am collecting enough material to write a book about the history of encoding, rather than just a short article about Unicode! I think that much of this material has general interest, so I will post a RESUME of all the answers as soon as I see that the thread has expired. *** I assume that I CAN RE-POST the PRIVATE ANSWERS that I received. If any of the authors wishes me to not republish their messages or part of them, or wish to remain anonymous, please let me know separately. *** Most of the answers, of course, are contained in Magda Danish's yet unpublished summary of Unicode history. When the case, I will simply refer to "the Unicode history on the Unicode web site"; everybody will be able to read it as soon as it will be completed and published. _ Marco