[1] [CITE@en-US[Selectors API Level 1]]
( ([TIME[2013-02-22 02:57:52 +09:00]] 版))
<http://www.w3.org/TR/2013/REC-selectors-api-20130221/>

[2] [CITE[IRC logs: freenode / #whatwg / 20140409]]
( ([TIME[2014-04-10 13:28:16 +09:00]] 版))
<http://krijnhoetmer.nl/irc-logs/whatwg/20140409#l-604>