[1] Web Controls 1.0 (2004-11-09 08:49:52 +09:00 版) http://www.whatwg.org/specs/web-controls/current-work/#user-focus-select

[2] Web Controls 1.0 ( (2004-11-09 08:49:52 +09:00 版)) http://www.whatwg.org/specs/web-controls/current-work/#focus0

[3] Web Applications Markup Language 1.0 ( (2004-04-08 02:39:12 +09:00 版)) http://hixie.ch/specs/html/apps/web-apps-1#focus0