[1] [CITE@en[Web Applications 1.0 r5695      Define how we create a 'specified CSS element reference identifier'. This maybe should move from HTML to CSSOM.]]
( ([TIME[2010-12-02 09:09:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=5694&to=5695>

[2] [CITE@en[Web Applications 1.0 r7722     Try to define order for supported property names. This is not based on testing. If there are compatibility constraints here that prevent implementing this as specced, please let me know.]]
( ([TIME[2013-02-13 09:03:00 +09:00]] 版))
<http://html5.org/tools/web-apps-tracker?from=7721&to=7722>

[3] [CITE@en[Remove unimplemented document.cssElementMap · whatwg/html@797b4d2]]
([TIME[2015-10-18 23:25:30 +09:00]] 版)
<https://github.com/whatwg/html/commit/797b4d273955a0fe3cc2e2d0ca5d578f37c0f126>