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

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

[3] InternetExplorer - 一部のブラウザでは $$() と document.querySelectorAll() で等価ではない - Qiita (2015-10-23 13:37:32 +09:00 版) <https://qiita.com/tom_konda/items/864e285defc1b17f7a0e>

[4] Align with changes in Selectors ( (annevk著, 2016-06-10 16:44:08 +09:00)) <https://github.com/whatwg/dom/commit/1594aa52357371354780750413ad88e9e8a2b56b>