`  ==Duplicate article== Blast! I've just spent a day writing an article on the ``X System``, ss my reference book (see 'Further reading' I just added) calls it, only to discover that we already have an article on this topic, just one which wasn't listed under all its names.  Which raises the question of what we ought to call the article. Both the Bell book, and the Turing bio by Hodges, which also covers it in some detail, call it the ``X System`` (or some typographical variant thereof, such as ``X-system``). Do we want to leave it here (which is, I gather, the name the NSA museum has it under), or use the one in all the references?   `