Actually this is a special case of my proposal to support  
relational operators.  Intersection is one useful operator; some  
others are:
   * Inverse: absorbing REV into REL
   * Product: independent typing of the two link ends
   * Join: indirect relationships (e.g., glossary's author)
While "," may be a good notation for Intersection, I don't want to  
see the REL value restricted to a comma-separated list.
See my post on "Links and Interactivity" for related comments.
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Paul Burchard	<burchard@math.utah.edu>
``I'm still learning how to count backwards from infinity...''
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