[1] [CITE@en[CSS Conditional Rules Module Level 3]]
( ([TIME[2012-09-11 09:24:30 +09:00]] 版))
<http://www.w3.org/TR/2012/WD-css3-conditional-20120911/>

[2] [CITE@en[Conditional Group Rules draft (better name needed)]]
( ([[L. David Baron]] 著, [TIME[2011-06-04 15:14:21 +09:00]] 版))
<http://lists.w3.org/Archives/Public/www-archive/2011Jun/0002.html>