[1] [CITE@en[HTML5 Revision Tracker]]
([TIME[2010-03-23 22:21:24 +09:00]] 版)
<http://html5.org/tools/web-apps-tracker?from=4859&to=4860>

[2] [CITE@en[HTML5 Revision Tracker]]
([TIME[2010-03-23 22:24:54 +09:00]] 版)
<http://html5.org/tools/web-apps-tracker?from=4860&to=4861>

[3] [CITE[Official Google Webmaster Central Blog: Google does not use the keywords meta tag in web ranking]]
( ([TIME[2011-12-17 11:28:33 +09:00]] 版))
<http://googlewebmastercentral.blogspot.com/2009/09/google-does-not-use-keywords-meta-tag.html>