american law
URN:lex illustrative examples
Here are some "worked examples" of URN:lex identifiers, to act as a guide for those implementing URN:lex on their sites. Discussion of this topic is taking place here.
United States
Federal law
Legislation
United States Code (per the Legal Information Institute):
For now, we are implementing US Code URNs inside <meta> tags, along the lines of the following example: