[1]
[CITE[Beyond Standards &#8211; Input placeholders]] <http://www.beyondstandards.com/archives/input-placeholders/>
([[名無しさん]])


[2]
[[Web Forms 2.0]] 仕様書の[[注釈宣言]]によれば、
[[Ian Hickson]] は将来の WF への追加の候補として考えているようです。
([[名無しさん]] [WEAK[2006-10-01 08:28:04 +00:00]])

[3] [CITE['''['''whatwg''']''' <textarea placeholder="">]] ([TIME[2009-03-30 19:44:44 +09:00]] 版) <http://lists.whatwg.org/htdig.cgi/whatwg-whatwg.org/2009-March/019086.html>

[4] [CITE@en[(X)HTML5 Tracking]]
([TIME[2009-08-23 16:05:44 +09:00]] 版)
<http://html5.org/tools/web-apps-tracker?from=2408&to=2409>

[5] [CITE@en[Opera: Opera 11.00 for Windows changelog]]
( ([[Frank M. Palinkas, Technical Writer, Opera Software ASA]] 著, [TIME[2011-04-24 11:17:12 +09:00]] 版))
<http://www.opera.com/docs/changelogs/windows/1100/>