[1] manakai's Conformance Checking Guideline for Obsolete HTML Elements and Attributes ( ( 版)) <http://suika.suikawiki.org/www/markup/html/exts/manakai-obsvocab>
[2] manakai's Conformance Checking Guideline for Obsolete HTML Elements and Attributes () <https://manakai.github.io/spec-obsvocab/>