* 歴史

** css3-ui

[REFS[
- [2] [CITE@en[CSS3 module: Basic User Interface]] ([[Tantek Çelik]] 著, [TIME[2002-08-03 07:13:43 +09:00]] 版) <http://www.w3.org/TR/2002/WD-css3-ui-20020802/#pseudo-choices>
- [3] [CITE@en[CSS3 Basic User Interface Module]] ([[Tantek Çelik]] 著, [TIME[2003-07-04 02:51:33 +09:00]] 版) <http://www.w3.org/TR/2003/WD-css3-ui-20030703/#pseudo-choices>
- [4] [CITE@en[CSS3 Basic User Interface Module]] ([[Tantek Çelik]] 著, [TIME[2004-05-12 02:17:47 +09:00]] 版) <http://www.w3.org/TR/2004/CR-css3-ui-20040511/#pseudo-choices>
- [1] [CITE@en[CSS Basic User Interface Module Level 3 (CSS3 UI)]] ([[Tantek Çelik]] 著, [TIME[2011-09-29 17:32:08 +09:00]] 版) <http://dev.w3.org/csswg/css3-ui/#pseudo-choices>
]REFS]

[5] 他の [[css3-ui]] の[[擬似要素]]とは違って [[XForms]] の仕様書には登場しません。