Jeff - I believe you're looking for the October 1985 article series in Computerworld, by Codd, entitled:
Does your DBMS Play by the rules
From Codd's own description it's the first time he went into all 12 rules in a single article. The first article is the base definition of the 12 (and rule 0), with a follow-on article to describe the details and corrolary rules.
As far as I know, it's still under copyright, so I can't post copies.
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Your lack of planning does not constitute an emergency on my part...unless you're my manager...or a director and above...or a really loud-spoken end-user..All right - what was my emergency again?