hyperlinking
URN:lex
URN:lex is a proposed Internet standard for legal document identifiers written by Pierluigi Spinosa, Enrico Francesconi, and Caterina Lupo. It is intended to coexist with (and provide important infrastructure for) more semantically-laden approaches like LegisLink and Citability.
The URN:lex proposal is here.
Citer
Citer is a project under development at the Legal Information Institute (project details).