[1] Web Controls 1.0 (11/8/2004, 11:49:52 PM 版) <http://www.whatwg.org/specs/web-controls/current-work/#user-focus-select-unknown>
[2] Web Controls 1.0 ( (11/8/2004, 11:49:52 PM 版)) <http://www.whatwg.org/specs/web-controls/current-work/#focus0>
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